Wegweiser Barrierefreiheit: Leitfaden zur Erstellung von Inhalten für Blinde bzw. Sehbeeinträchtigte

It is an ethical and legal obligation to provide accessible content to blind and visually impaired people. The following information is intended for our authors, editors, contributors to book projects, and anyone interested in learning more about accessible publishing.

There are three dimensions to accessibility: the content, special layout and structural elements (such as tables, images, diagrams, formula environments), and the technical format such as Portable Document Format (PDF) or Electronic Publication Format (EPUB).

It is especially important to use the standard features of your word processing program for all semantic or highlighted content, layout, and structural elements. In Word, for example, use the appropriate styles "Heading 1", "Heading 2", etc. for headings instead of manually setting the font to "large and bold". This is the only way that blind people, for example, can use a screen reader to quickly jump from chapter to chapter and use these structural elements for orientation.

Alternative text is required for all images, diagrams, and formulas for the blind. These must be true descriptions of the content to be seen, not just repetitions of the image caption. Colorblindness must also be considered. Please do not use charts that can only be interpreted by the selected colors, and do not use additional patterns or display variations such as dotted lines, dashed lines, or the like. Avoid complex or nested tables, as these are often difficult for screen readers to read clearly.

In terms of technical format, PDF is the least accessible because a lot of information can be lost when converting from Word. For example, the correct reading order for screen readers or structural markers such as section breaks. In addition, making PDFs accessible in accordance with standards such as ISO 14289-1 and WCAG (Web Content Accessibility Guidelines) requires a great deal of work.

This cannot be done by FAU University Press, so please refer to service providers (see below). The Hypertext Markup Language (HTML) or Electronic Publication (EPUB) formats are more suitable. We would like to invite you to participate in the beta test of the Open Source Academic Publishing Suite (OS-APS) and SciFlow Publish: https://www.university-press.fau.de/en/publizieren/betatest-der-open-source-academic-publishing-suite-os-aps-und-sciflow-publish/. This will allow you to create dynamic formats.

Below you will find tips on how to make the final formats accessible, or at least as accessible as possible, or how to support this with simple measures or service providers.

External service providers

If the steps described below for preparing and creating accessible documents are too time-consuming for you, but you still want to ensure the digital accessibility of your planned eBook, you can hire a service provider of your choice. They will take on the task of creating an accessible PDF.

Please use the FAU University Press Book Submission Form to let us know at the beginning of the book project if you prefer a specific service provider. Otherwise, we usually work with one of the following two vendors.

Especially if you have or can apply for third-party funding for the book, we strongly recommend this option, as more and more third-party funders support digital accessibility and open access to research results.

Below are examples of two trusted partners. Of course, we can respond to your wishes and requests and commission others.

Amnet Accessibility Services

Amnet is a service provider in almost all areas of digital publishing. Because certain accessibility requirements are increasingly beyond the capacity of smaller publishers such as FAU University Press, Amnet offers services that include accessible metadata generation, semantic structuring, table tagging, MathML generation, content accessibility, and even writing alt text descriptions. Amnet can prepare your e-book as an accessible PDF in accordance with the most important standards and checking tools, and can also deliver accessible EPUB files.

The costs vary depending on the effort. As a guideline, it would have cost about 200€ to buy volume 427 of FAU Studien aus dem Maschinenbau (https://doi.org/10.25593/978-3-96147-667-1) via Amnet according to WCAG standards. And just under €150 to also create an accessible EPUB file from the PDF. The book had 210 pages. Please do not take these amounts as a flat rate for similar documents; more pages, poorer preparation, or more complex content will increase the price.
BBSB e.V. BIT-Zentrum

According to the ISO standard PDF/UA and the BITV 2.0 (Barrierefreie Informationstechnik-Verordnung), the Beratungs-, Informations- und Textservice (BIT) of the Bayerischer Blinden- und Sehbehindertenverband (BBSB) can convert your publications into accessible formats for the blind and partially sighted. After completion and thorough testing with the latest version of the PAC (PDF Accessibility Checker) and blind IT experts, you will receive your accessible PDF back.

In addition to the PDF versions, the books are also available in Braille, large print and audio formats. The price list can be found at https://www.bit-zentrum.bbsb.org/unser-angebot/individueller-textservice/ (in German only). Non-accessible PDF documents are charged at $74.00 per hour of work.

It would have taken about 7 hours to complete the above mentioned volume 427 of the FAU Studien aus dem Maschinenbau (https://doi.org/10.25593/978-3-96147-667-1). Please do not take this as a flat rate for similar documents. Since each file is structured differently, the BIT Zentrum must examine each document in detail before a realistic quote can be provided.

From Word to accessible PDFs

The following guide with images is largely based on Müller, Emma; Voegler, Jens (2020): Barrierefreie Dokumente – Anleitung zur Erstellung barrierefreier PDF-Dokumente mit Word. Technische Universität Dresden. Available online at https://nbn-resolving.org/urn:nbn:de:bsz:14-qucosa2-739676. Content is licensed under the CC BY-NC-SA 4.0 License. Truncations and changes have been made. Unless otherwise noted, changes are also licensed under CC BY-NC-SA 4.0. If you prefer a video, we recommend "From Word to PDF" by the Publications Office of the European Union (https://www.youtube.com/watch?v=9n-insewE10).

This section provides specific instructions for converting your Word document into an accessible PDF. The instructions include the main steps you should follow when creating an accessible document: Setting document properties, performing text editing and image description, creating the PDF document, and finally checking it.

Following the guidelines does not automatically guarantee an accessible PDF document. Further specific checks are required, e.g. with the PDF Accessibility Checker (see also Checking tools below).

This guide refers to Word on Windows. There are some differences for Word on MacOS that can be found in the original document referenced above.

Activate accessibility check

Since Office 2010, a built-in accessibility checker has been available in all Office applications. As of Word 2019, there is an Accessibility Check menu item on the Check ribbon. If you keep the Accessibility Check window open after you turn on the accessibility check, you can see any accessibility issues in real time as you write.

You can also run the accessibility check later as a separate step before exporting the PDF. For more information, see "Accessibility check with Office" below.

Default Templates

Each document has default styles for each text element. In the Styles group of the Ribbon you will find the Quick Styles list, which contains a selection of all available styles. If you open the Styles pane from the toolbar and select Select styles to display: all, a list of all styles available in the document will be displayed. To apply a style to a section of text or a heading, select the text and then select the desired style.

Document Properties

Document title

If your document has a title, it will later appear as the window title of your PDF document. People who rely on screen readers will hear the window title read aloud and know which document it is. Figure 1 and Figure 2 show the process.

Enter any meta information about the document. In addition to the title, you can add other information that describes the document in more detail. However, the title is primarily important for accessibility.

Figure 1 Location of the File Tab on the Ribbon in Windows

Figure 2 Setting the Title in the Document Properties in Windows
Document language

Every Word document has a base language in which it is written. This feature is especially important for people who use screen readers. In Word, you can change the language of the document from the status bar (see Figure 3).

If your document contains sections or individual words that differ from the default base language, you should change the language for these sections or words, otherwise they will not be correctly reproduced by the screen reader. To do this, select the desired text and follow the instructions above.

Figure 3 Status bar language setting

Word Processor

After these preparations, you can start the real work: creating the content. All visual properties of the text (font size, color, spacing, paragraphs, etc.) should be organized in style sheets. Avoid positioning text with spaces and empty lines. You can check your document for existing spaces and lines by displaying the formatting marks (Figure 4).

Abbildung 4 Formatierungszeichen ein-/ausblenden — Figure 4 Show/Hide Formatting Characters

Avoid manual or automatic hyphenation in your document. These are usually not implemented correctly when converted to PDF. Select "none" for the hyphenation options. Also, you should always use Word's multi-column feature, and not, for example, frameless tables.

When a separate (free-form) text box is used to highlight information, it is usually visually related to the adjacent text or image. In order for this relationship to be represented structurally, the appropriate "anchor" must be placed in the correct position. To do this, drag the anchor icon that appears when you select the text box onto the paragraph to which the text box belongs. The content of the text box will then be placed after the text of that paragraph in the reading order.

Please note that the frame of the text box will be recognized as an image element during conversion to PDF, so you should provide the text box with an alternative text. Please also make sure that the anchor is set to the correct position for all images or that the line break option "With text in line" is selected so that the reading order of the elements corresponds to the optical reading order when converting to PDF.

Paragraphs

Simple text passages in your document should be formatted as such. The corresponding style sheet is usually called Standard.

Depending on how you want your document to look, you can create different variants of the template. FAU University Press, for example, uses two variants: "FUP Fließtext Standard" and "FUP Fließtext mit Einzug".
Headings

Headings are the most important navigation and orientation elements for blind people to read content in a structured way. Word provides good conversion to PDF in this area. Headings are already defined in the standard formats and can be used like normal style sheets.

FAU University Press has named some of them, so they are called "FUP Überschrift 1," "FUP Überschrift 2," and so on. In the outline view, check that you have used the headings correctly and that the hierarchy of heading levels is correct.
Numbering and Lists

To create lists, use the predefined list styles in Word. You can find the list styles on the Home tab in the Paragraphs group.

The visible bullet symbol is often not read aloud by screen readers for the blind. Therefore, the bullet symbol itself should have no meaning. For example: Presenting a positive-negative list with plus and minus signs is inappropriate. Such additional information should be clear from the text.
Links and cross references

Links or cross references in the document must be active links. In the source document, such active elements can be activated with Ctrl+click and lead to the referenced element. For cross-references, set the alternative text of the hyperlink via Tooltip..., e.g. the title of the website or a short description. Do not use generic terms or phrases such as "hyperlink" or "click here.
Table of Contents (TOC)

Similar to headings, tables of contents provide overview, orientation, and navigation. With Word, you can automatically create TOCs that provide active navigation similar to a list when you convert to PDF. This requires that you have created headings using style sheets as described in this guide. First, navigate to the location in the document where you want to place the TOC. From the Links tab, you can insert a table of contents.

Tables of contents are active links. This means that they point to a specific piece of text. Tables of contents are active because you can select an entry to jump to the desired location in the document. Before publishing, you should make sure that all active links work correctly. It is important to keep your tables of contents up to date.
Tables

If the document contains tables, special care must be taken to structure them logically so that they can be read and understood by blind people: In the simplest case, they navigate from cell to cell using the keyboard and have the contents read to them. In the simplest case, they can navigate from cell to cell using the keyboard and have the content read aloud to them. In this case, they can recognize which cells are headings and thus understand what the individual pieces of information in the cells mean - provided that the table has the necessary structure and has not been converted to tabular form solely visually.

Pseudo tables simulated by tabs and spaces in Word should be avoided at all costs. The only reliable way to create tables in Word is to use Word's table tool.

You must always select the header row or the first column of the table as the heading. This is where you specify whether your table has a header row or a first column, or a combination of both. Word recognizes a multi-page table as multiple tables when it converts it to a PDF document. Therefore, you must make sure that the header row is repeated on each page. To do this, select the Repeat the same header row on each page option on the Rows tab of the Table Properties window.

Note: Complex, multidimensional, and nested tables are difficult or impossible for blind people to read. If possible, complex tables should be broken into several simple tables to ensure readability and accessibility. Alternatively, a meaningful description of the table should be included in the alternate text.

Images

Adequate color contrast

If you are creating your own illustrations or diagrams, make sure there is enough color contrast (e.g., text on a colored background) and keep in mind that some people have difficulty recognizing different colors (e.g., red-green blindness). A tool that can help you with this is ColorBrewer (https://colorbrewer2.org), which you can use to select appropriate color combinations.
Characteristics of Good Image Descriptions
It should be noted that images and graphics require a meaningful alternative description in order to be accessible to blind people. A good image description should have the following characteristics

Objectivity (no personal interpretation)

Comprehensibility (considering the target audience)

Meaningfulness (the description needs to make sense both in and out of context)

Didactic clarity and consideration

Efficiency (keep information complete, but short and concise)

The image description should be structured consistently and in a strict order according to the type of graphic. The internal reading flow of the graphic should be taken into account. It is recommended to build the description from the broad and general to the fine and specific. An image description should enable non-visual readers to obtain all the information necessary for the purpose of the graphic. The following information should be included in the description, depending on the context and purpose of the image:

Intention/purpose of the image

Picture situation or location

Objects, Buildings, People

Emotions, Atmosphere

What happens in the image?

Colors (in diagrams, however, the description of visual attributes is only required if they provide additional information)

Only include information that is not otherwise accessible, for example, do not simply repeat the caption. Routledge Publishing provides authors with very clear examples of appropriate alternative text: https://www.routledge.com/our-customers/authors/publishing-guidelines/accessible-content.
Defining alternative text for images in Word
As of Word 2019, there is an alternative text toolbar that can be used to add an alternative description to an image. You can open it from the shortcut menu (for example, by right-clicking the image). Enter a meaningful description of the content. Decorative images that do not provide content-relevant information can also be marked as decorative at this point. In this case, they will be ignored by assistive technologies. Since Word 2019, it is also possible to automatically generate alternative text for images (function: Generate description for me). However, these alternative texts are currently not very meaningful, so we do not recommend using this feature. If possible, avoid using SmartArts. In the current version, Word generates multiple images from a SmartArt when converting to PDF and does not apply the alternative texts set on the SmartArt. Save the SmartArt as an image and paste it into the document instead. You should also insert charts as images because not all chart elements are labeled correctly when converted to a PDF document. Use the following structure to describe the diagrams:

Overview: Title, chart type, general content, special features such as alignment;

Axes: Arrangement, labeling, unit, scale (range, intervals), axis intersections;

Data, depending on the chart type, for example: number of data series, name and arrangement of the data, description of rough trends, specific data values (in tabular form if possible).

Depending on the purpose of the diagram and the description, subjective statements about the content of the diagram may be included in the diagram description. However, these must be marked as interpretation or personal interpretation.
Decorative images (decorative graphics)

Check accessibility with MS Office

Before exporting a Word document to PDF and then having to make time-consuming improvements to the PDF document, it is worthwhile to run an internal Office check for accessibility issues before exporting. However, fixing problems in Office does not mean that there will be no problems in the exported PDF document.

Since Office 2010, a built-in accessibility checker is available in all Office applications. Starting with Word 2019, there is a menu item on the Check ribbon tab. In older versions, the check is started from the file information. The Accessibility toolbar opens in the right sidebar. At the top of the toolbar is a list of errors and warnings, grouped by type. Clicking on an error or warning immediately selects the affected item, so you do not have to search for it first. Below the list is an area that provides more detailed information about the selected error. Here you will also find the reasons why the correction is necessary and instructions on how to correct the error.

Create a PDF document

Now all you need to do is export your document as a PDF (Figure 5). We do not recommend using a PDF printer because it does not export the logical structure.

Abbildung 5 Exportansicht von Word unter Windows — Figure 5 Export in Word on Windows

In the Create PDF / XPS dialog box, you can specify the file name, file type, and location for the final publication. As an alternative to the steps described above, you can also open this dialog by pressing the F12 key, but then you must select PDF as the file type. PDF export settings can be made using the Options button in the dialog. Set the following options. Confirm with the Ok button and save the document with the Publish button.

Option "Create bookmarks using: Headings": All headings will be converted to bookmarks if you have worked with style sheets and used headings accordingly.
Option "Document Properties": Adds information to the PDF, such as the title of the document.
Option "Document structure tags for accessibility": All structure information is transferred to the PDF.
Disable "Bitmap texts when fonts [...]". This would cause text content to be saved as image information, making it unreadable to non-visual users.

Create accessible PDFs from LaTeX

Unfortunately, LaTeX is currently rather unsuitable for creating accessible documents and should be avoided. Packages introduced in the past such as accessibility (https://ctan.org/pkg/accessibility) or axessibility (https://ctan.org/pkg/axessibilityare no longer fully developed and will no longer be maintained.

There is a new experimental package called tagpdf (https://ctan.org/pkg/tagpdf) that provides tools for experimenting with tagging and accessibility using pdfLaTeX and LuaTeX. It works partially for simple documents, limited to standard classes, standard commands, and already supported packages. The more complicated the document and the more external packages it contains, the more likely it is to have problems. Accordingly, tagpdf is not yet integrated into the FAU University Press templates, and we have not yet been able to get it to work correctly.

There are a few websites that give general recommendations and tips on accessibility in LaTeX outside of special accessibility packages. However, most of these are outdated. Lewis Forbes' blog "LaTeX and Accessibility" is a relatively up-to-date resource (https://blogs.ed.ac.uk/isintern/2023/08/15/lewis-forbes-latex-and-accessibility/). Hier wird teilweise auch beschrieben, was nicht mehr funktioniert, z.B. Alternativtexte über das oben genannte Accessibility-Paket. Laut Lewis Forbes kann man Alternativtexte derzeit noch über diese beiden Wege hinterlegen:

„Using a parameter on caption \caption[alt text]{caption text} […]. This should be used when \includegraphics{} is used within a \figure{} environment.
Using \pdftooltip{} from the pdfcomment interface successfully added tooltips with user-specified text to the document, which Ally recognized as alt text. This should be used when \includegraphics{} is being used with no \caption{}. For example, I used it in a \subfloat{} environment.“

In an example based upon the DOI: 10.1090/noti2606 page 70, the latter procedure could be as follows: a square is drawn and provided with alternative text:

\usepackage{pdfcomment}

\pdftooltip{

\begin{tikzpicture}

\draw (0,0) — (1,0) — (1,1) — (0, 1) — (0, 0);

\end{tikzpicture}

}{Here is a square rectangle with black lines, without colored filling.}

The title and language of a PDF document can be specified by the following lines in the preamble of the document:

\usepackage{hyperref}

\hypersetup{pdftitle={Document Name}, pdflang={en-GB}}

In general, however, the recommendation mentioned at the beginning applies: If you want a PDF that is as accessible as possible, please use Word and the Word recommendations mentioned here to create your manuscript, or, in the case of LaTeX documents, plan to hire a service provider to do the final preparation.

Support provided by SciFlow Publish and OS-APS or OS-APS_STEMO

The project "Ausbau der Open Source Academic Publishing Suite für komplexe STEM-Publikationen und optimierte Online-Darstellungen" supports digital accessibility in several areas.

In the future, OS-APS (https://os-aps.de/) and SciFlow Publish will integrate accessibility checking functionality, and the planned JATS/BITS reader will support popular screen readers, making content accessible to blind and visually impaired people on almost any device without conversion.

With OS-APS you can generate HTML files from your manuscripts. You can then check and optimize the HTML e-book using the checking tools (see below) or the Web Accessibility Checker. XML exports are also possible with OS-APS. With the help of tools such as Calibre (https://calibre-ebook.com/), it would also be possible to generate an EPUB e-book from the HTML or XML file.

FAU University Press has also licensed a trial version of the commercial software SciFlow Publish, which can be used to generate EPUB files directly. Join the beta test of SciFlow Publish: https://www.university-press.fau.de/en/publizieren/betatest-der-open-source-academic-publishing-suite-os-aps-und-sciflow-publish/.

Testing Tools

To avoid misunderstandings, files that are classified as accessible by the test tools are usually only compliant with the underlying technical standards (e.g. ISO 14289 (PDF/UA) or W3C Accessibility Standards such as WCAG). In practice, however, they can still be unusable for blind people due to poor alternative texts, for example. Accessibility must therefore be based on actual usability for people with disabilities. See, for example, the section "Characteristics of Good Image Descriptions" under "From Word to accessible PDFs".

For accessible PDF files

For help fixing bugs found by the following testing tools, see the page "Barrierefreies Webdesign". (https://www.barrierefreies-webdesign.de/knowhow/pdf-ua/). Simply paste the error message into the search field and follow the step-by-step instructions using Adobe Acrobat Pro.

It is also advisable to intellectually check the reading order of the PDF - either by viewing it in Adobe Acrobat Pro ("Order" in the left column), or by reading the document with the help of Adobe Acrobat's speech output or a freely available screen reader such as NVDA (https://nvda.bhvd.de/) vorlesen lässt.

PDF Accessibility Checker (PAC) 2024

PDF Accessibility Checker (PAC) is a Windows program that checks the technical accessibility of PDF documents and is available at https://pac.pdf-accessibility.org/en/download . The program does not require installation and can be run without administrator rights in work environments such as universities. After opening the PDF document in PAC, checkpoints for quality as well as PDF/UA and WCAG conformance are displayed in various tabs, e.g. in the context of alternative descriptions, metadata, structural elements or document settings. Additional quick guides and explanations can be found at https://pac.pdf-accessibility.org/en/resources. The software is provided free of charge by the vendor. It is therefore considered freeware, but not open source.
Commonlook PDF Validator

The CommonLook PDF Validator is a free tool that can be requested from https://allyant.com/commonlook-accessibility-suite/cl-pdf-validator/ and can be integrated directly into Adobe Acrobat as a plug-in. This means that the document is automatically checked for accessibility according to WGAC and does not need to be exported to a separate program. In addition, you receive a certification report as proof that the file actually conforms to the standards. Many problems can be solved directly with the plugin.
PAVE

Another interesting alternative that not only allows you to check PDF documents for accessibility, but also to edit the errors and warnings displayed, is the online tool PAVE (https://pave-pdf.org/?lang=en). The tool is currently outdated as of 2016, but a new version should be available soon.

The application runs in the browser, no download is required. PAVE can be used to add metadata such as the language and title of the document, and to check and change the reading order of the tags. Unfortunately, the maximum file size is limited to 5 MB, so the tool is not suitable for large or image-rich documents. FAU University Press publications that are larger than 5 MB can be split into smaller pieces using Adobe Acrobat Pro, for example. These can then be reassembled using PAVE. A video tutorial on PAVE can be found here: https://www.youtube.com/watch?v=zV74gxcwQ58.

Given the effort and the outdated technology of PAVE as of 2016, the process is currently experimental and not recommended for regular use - at least for now. However, we have already tested the new version and it looks very promising. We will link to it here and cover it as soon as it is online.
Checklist "Barrierefreies PDF - Relevante Prüfschritte" from the German Publishers and Booksellers Association (Börsenverein des Deutschen Buchhandels e.V.)

For accessible EPUBs

Ace by DAISY

Ace is a tool that can be downloaded from https://daisy.org/activities/software/ace/ as a command line utility or as an executable program (for MacOS, Windows, and Linux) to check EPUB files for compliance with the W3C EPUB Accessibility Standards.
Several tabs display violations of the standard according to their severity, missing metadata, a comparison of the heading hierarchies with the HTML structure to help detect "Untitled BODY", for example, and missing attributes such as alternative texts for images.

For more information, visit https://daisy.github.io/ace/ and https://daisy.github.io/ace/getting-started/ace-app/.
Born Accessible Content Checker (BACC) from Deutsches Zentrum für barrierefreies Lesen (dzb lesen)

BACC is another tool for the validation of EPUB files in accordance with the W3C EPUB Accessibility Standard. The application runs in the browser (https://bacc.dzblesen.de/), no software download or installation is required.

Various tabs report on policy violations, missing metadata, heading levels versus the structural HTML structure to help identify "Untitled BODY," for example, and missing descriptions such as alternative text for images.

For more information, see the i icon for "About the Verification Tool" and https://www.dzblesen.de/ueber-uns/fachthemen-kooperationen-projekte/inklusives-publizieren(German only). You will also find an EPUB3 eBook guide .
pagina EPUB-Checker based on the W3C open source software EPUBCheck

The pagina EPUB-Checker is a checking tool from the German company "pagina GmbH Publikationstechnologien", which is based on the open source software EPUBCheck from the W3C.

The pagina EPUB Checker encapsulates this open source software in a multilingual user interface and offers additional features such as validation of unzipped (not zipped) EPUB files. The tool can be downloaded from https://pagina.gmbh/startseite/leistungen/publishing-softwareloesungen/epub-checker/ as an executable program for Mac, Windows and Linux. It also runs portable on a USB flash drive. The results window shows whether the EPUB file contains problems or errors, in which file or line the error occurs, and a description of the error.

For accessible HTML eBooks

Visit the W3C Web Accessibility Initiative (WAI) Web site for a comprehensive list of Web accessibility evaluation tools: https://www.w3.org/WAI/test-evaluate/tools/list/For a quick guide to choosing an appropriate tool, visit https://www.w3.org/WAI/test-evaluate/tools/selecting/. For a free browser-based tool, see the following WAVE Web Accessibility Evaluation Tool:https://www.w3.org/WAI/test-evaluate/tools/selecting/) bietet eine kurze Anleitung zur Auswahl eines geeigneten Tools.. Für ein browserbasiertes, kostenloses Tool siehe nachfolgendes WAVE Web Accessibility Evaluation Tool:

WAVE Web Accessibility Evaluation Tool

WAVE includes assessment tools to help authors make their web content more accessible to people with disabilities. WAVE can detect many errors according to the Web Content Accessibility Guidelines and checks the WCAG 2 checklist from WebAIM (https://webaim.org/standards/wcag/checklist).

You can use WAVE by entering the URL of the HTML page or HTML eBook (e.g. the *.json page generated by OS-APS) in the field provided on https://wave.webaim.org/ . In the subsequent WAVE report, various warnings and explanations can be displayed as details in a preview that overlaps the HTML eBook; you can also check reading sequences, structures (such as headings, tables, list formats), color contrasts, and more. The code can also be displayed next to the preview.

Accessibility Guide: Guidelines for Creating Content for the Blind or Visually Impaired