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European Accessibility Act enforced since June 2025

Free alt text checker — then fix it in one click

Paste any URL. Alta grades every image on the page against WCAG 2.2, then writes the missing alt text for you.

Free and unlimited — no signup. We read the page's HTML and grade every <img>. Generating fixes uses your 5/day free quota.

Missing alt text is the single most common accessibility failure on the web — WebAIM's 2026 analysis found problems on more than half of the pages it tested. Most checkers stop at telling you that. Alta grades the page and writes the fix, including proper long descriptions and data tables for charts and infographics.

How to use it

  1. Paste the URL of a page you own and press Check page.
  2. Review the score and the per-image issues.
  3. Add one line of context (what the page is about) — it measurably improves the output.
  4. Press Generate on any flagged image, then copy the alt text or the ready-to-paste HTML.

What does the alt text checker look for?

Missing alt attributes, filename-style alt text (IMG_1234.jpg), generic values like 'image' or 'logo', alt text over 125 characters, redundant 'image of' prefixes, and the same alt text duplicated across different images.

Is the checker really free?

Yes — scanning a page is unlimited and needs no signup, because it only reads your HTML. Generating replacement alt text uses AI, so it draws on the free daily quota or a Pro license.

Does alt="" count as an error?

No. An empty alt is the correct markup for decorative images, so we list those separately as 'verify' rather than failing them.

Can it fix the problems it finds?

Yes. Every flagged image gets a one-click generate button that writes WCAG-compliant alt text — plus a long description and data table for charts and infographics — which you can copy or export as CSV.

Built for the images other tools give up on

📊 Charts & infographics

Per the W3C's Complex Images guidance, a chart needs a short alt and a long description. Alta writes both — plus an HTML data table of the values it reads off the chart.

🧭 Context-aware

The usual complaint about AI alt text is that it describes pixels instead of purpose. Tell Alta what the page is about and it writes to the image's function.

🙋 Honest about doubt

If a label was too small or a value ambiguous, Alta says so instead of inventing it — so your human review goes to the images that need it.

Why alt text, why now

⚖️ It's the law

The European Accessibility Act applies since June 2025, and 2026 is the first full year of national supervision — with corrective-action notices already landing.

🔍 It's free SEO

Google Images drives ~20% of web searches, and AI answer engines lean on alt text to understand what your visuals show.

♿ It's the right thing

2.2 billion people live with visual impairment. Alt text makes your content usable for everyone.

Not sure which of your images are missing alt text?

Paste a URL into the free checker — it grades every image on the page, then fixes them one click at a time.

Run the free alt text checker →

Pricing

Free
$0
  • 5 images / day
  • Unlimited page scans
  • All 3 styles & 13 languages
  • No signup
Start free
Pro
$29/year
  • Unlimited generations
  • Bulk upload (50 at once)
  • CSV export for your CMS
  • Commercial use · support
Get Pro license →

FAQ

Is the generated alt text WCAG 2.2 compliant?

Yes — output is kept under 125 characters, avoids "image of" prefixes, and describes function and content per WCAG 2.2 SC 1.1.1. Complex images additionally get the long description the W3C asks for.

How does it handle charts and infographics?

It detects them and returns three things: a short alt for the alt attribute, a long description that transcribes the labels, units and figures, and an HTML data table of the values. Copy the ready-to-paste <figure> snippet and the whole thing is wired up with aria-describedby.

Do I still need to review the output?

Yes — every AI alt text tool needs a human pass, and Alta is built to make that pass short: it flags what it could not read reliably instead of guessing, and it tells you when an image looks decorative and should get alt="".

Do you store my images?

No. Images are processed in memory and never stored.

How does the Pro license work?

Buy once on Gumroad, paste your license key in the tool. Instant activation, works in any browser.