PDF1 Image with alt text Screen reader compatibility

PDF WCAG
Dec 12, 2023

Expected Result: works in a screen reader

Actual Result: causes problems in 24 screen reader / browser combinations

WCAG Technique: PDF1 Applying text alternatives to images with the Alt entry in PDF documents

Code used for this test:


		<a href='SR_PDF_alt_text.pdf'>SR_PDF_alt_text.pdf</a>
	

Reliability Trend

This graph shows reliability over time for this code in NVDA, JAWS and Voiceover. Other screen readers don't have enough historical data yet to plot trends.

100%80%60%40%20%0%201520162017201833%201950%202050%202150%202250%202343%

Change History

Last updated: December 12, 2023

  • Bad NVDA with Chrome Causes problems from NVDA 2018.4 to NVDA 2023.3
  • Good NVDA with IE Stable - OK from NVDA 2017.3 to NVDA 2019.2
  • Bad NVDA with FF Causes problems from NVDA 2018.4 to NVDA 2023.3
  • Bad JAWS with Chrome Causes problems from JAWS 2018.1811.2 to JAWS 2023.2311.34
  • Good JAWS with IE Stable - OK from JAWS 17.0.2007 to JAWS 2019.1912.1
  • Bad JAWS with FF Causes problems from JAWS 2018.1811.2 to JAWS 2023.2311.34
  • Good VoiceOver macOS Stable - OK from VoiceOver macOS 10.14 to VoiceOver macOS 13.6
  • Good VoiceOver iOS Stable - OK from VoiceOver iOS 12.4 to VoiceOver iOS 16.6
Screen readerBrowserModeNotesWhat the user hears
Fail NVDA 2023.3Chrome 120 Reading No description for graphic Graphic, unlabeled graphic.
Fail NVDA 2023.3FF 115 Reading Image ignored - but Firefox accessibility inspector shows figure named 'this is alt text' in accessibility tree
OK NVDA 2023.3Edge 120 Reading Graphic, this is alt text
Fail NVDA 2022.2Chrome 105 Reading No description for graphic Graphic, unlabeled graphic.
Fail NVDA 2022.2FF 102 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK NVDA 2022.2Edge 105 Reading Graphic, this is alt text
Fail NVDA 2021.2Chrome 94 Reading No description for graphic Graphic, unlabeled graphic.
Fail NVDA 2021.2FF 91 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK NVDA 2021.2Edge 94 Reading Graphic, this is alt text
Fail NVDA 2020.2Chrome 86 Reading No description for graphic Graphic, unlabeled graphic.
Fail NVDA 2020.2FF 78 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK NVDA 2020.2Edge 92 Reading Graphic, this is alt text
Fail NVDA 2019.2Chrome 79 Reading No description for graphic Graphic, unlabeled graphic.
Fail NVDA 2019.2FF 68 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK NVDA 2019.2IE11 Reading Graphic, this is alt text
Fail NVDA 2018.4Chrome 73 Reading No description for graphic Graphic, unlabeled graphic.
Fail NVDA 2018.4FF 60 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK NVDA 2018.4IE11 Reading Graphic, this is alt text
OK NVDA 2017.3IE11 Reading Graphic, this is alt text
Fail JAWS 2023.2311.34Chrome 120 Reading No description for graphic Unlabeled graphic.
Fail JAWS 2023.2311.34FF 115 Reading Image ignored - but Firefox accessibility inspector shows figure named 'this is alt text' in accessibility tree
OK JAWS 2023.2311.34Edge 120 Reading This is alt text.
Fail JAWS 2022.2207.25Chrome 105 Reading No description for graphic Unlabeled graphic.
Fail JAWS 2022.2207.25FF 102 Reading Alt text not read, but Firefox accessibility inspector shows figure with name 'This is alt text' Graphic
OK JAWS 2022.2207.25Edge 105 Reading This is alt text.
Fail JAWS 2021.2107.12Chrome 94 Reading No description for graphic Unlabeled graphic.
Fail JAWS 2021.2107.12FF 91 Reading Alt text not read, but Firefox accessibility inspector shows figure with name 'This is alt text' Graphic
OK JAWS 2021.2107.12Edge 94 Reading This is alt text.
Fail JAWS 2020.2008.24Chrome 86 Reading No description for graphic Unlabeled graphic.
Fail JAWS 2020.2008.24FF 78 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK JAWS 2020.2008.24Edge 92 Reading This is alt text.
Fail JAWS 2019.1912.1Chrome 79 Reading No description for graphic Unlabeled graphic, graphic.
Fail JAWS 2019.1912.1FF 68 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK JAWS 2019.1912.1IE11 Reading This is alt text, graphic
Fail JAWS 2018.1811.2Chrome 73 Reading No description for graphic Unlabeled graphic.
Fail JAWS 2018.1811.2FF 60 Reading Image ignored - Firefox accessibility inspector shows no images in accessibility tree
OK JAWS 2018.1811.2IE11 Reading Graphic, this is alt text
OK JAWS 17.0.2007IE11 Reading Graphic, this is alt text
OK VoiceOver macOS 13.6Safari 16.6 Reading This is alt text, image
OK VoiceOver macOS 12.5Safari 15.6 Reading This is alt text, image
OK VoiceOver macOS 11.5Safari 15.0 Reading This is alt text, image
OK VoiceOver macOS 10.15Safari 14.1 Reading This is alt text, image
OK VoiceOver macOS 10.14Safari 13.0 Reading This is alt text, image
OK VoiceOver iOS 16.6Safari 16.6Touch This is alt text, image
OK VoiceOver iOS 15.6Safari iOS 15.6Touch This is alt text, image
OK VoiceOver iOS 14.7Safari iOS 14.7Touch This is alt text, image
OK VoiceOver iOS 13.3Safari iOS 13.3Touch This is alt text, image, 1 of 1
OK VoiceOver iOS 12.4Safari iOS 12.4Touch This is alt text, image

Test notes

All tests were carried out with screen reader factory settings. JAWS in particular has a wide variety of settings controlling exactly what gets spoken.

Screen readers allow users to interact in different modes, and can produce very different results in each mode. The modes used in these tests are:

  • Reading Content read using the “read next” command in a screen reader
  • Tabbing Content read using the “tab” key in a screen reader
  • Heading Content read using the “next heading” key in a screen reader
  • Touch Content read when touching an area of screen on a mobile device

In the “What the user hears” column:

  • Commas represent short pauses in screen reader voicing
  • Full Stops represent places where voicing stops, and the “read next” or “tab” or “next heading” command is pressed again
  • Ellipsis … represent a long pause in voicing
  • (Brackets) represent voicing that requires a keystroke to hear