Images missing alt text
18.7%
of the 3,044 free scans considered in the last 30 days raised this finding. That is 569 scans across 568 distinct sites. 95% interval 15.7% to 22.1%.
What it means
Alt text is how a screen reader describes an image: without it, the image is invisible to a visitor who cannot see it.
How to fix it
Give every meaningful image an alt attribute describing what it shows. Decorative images get alt="" so screen readers skip them rather than reading a filename.
How to check it yourself
View source and check img tags for an alt attribute. Missing ones make that image invisible to a screen reader.
What fixed looks like
View source shows an alt attribute describing every meaningful image, and alt="" on decorative ones.
How we measured this
Go Voltic scans a site and records which findings it raises. The share above is over every free four-page scan in the last 30 days that loaded at least one page, which is 3,044 scans. Deep scans of paid reports and of the research sweep read a site at a different depth and are a separate population, never in this denominator. It is not a survey and it is not an estimate: it is a count of what our own scanner found. Sites are counted once each in the distinct-sites figure, so a site scanned twice does not weigh double there.
The interval is a 95% Wilson interval. A share printed without its sample size reads as certainty and is indistinguishable from a guess, so both are always shown. Figures on this page were computed on 2026-09-08.
The same share sits beside every other finding on the benchmarks page, which also carries the whole table as CSV and JSON and says how to cite it.
Check your own site
The free scan reads four pages and reports every finding it raises, including this one. It takes about ten seconds and asks for nothing but the address.