Syed Waleed

Paste your page HTML to find images missing alt text, empty alts, duplicates and filename-as-alt issues. Free SEO and accessibility check, no signup.

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Alt Text Checker

Paste any page's HTML to find images missing alt text, empty alts, filename-as-alt mistakes, and other issues hurting your SEO and accessibility.

100% private

Your HTML is analyzed inside your browser with zero uploads. Nothing is sent, stored, or shared.

No signup

No account, no email, no tracking. Paste, check, fix — that is the whole workflow.

Free forever

Unlimited checks on pages of any size, with no paywall and no limits.

How to use the alt text checker

  1. 1Get your page's HTML

    Open the page in your browser and view the source (Ctrl+U on Windows, Cmd+Option+U on Mac), then select all and copy it.

  2. 2Paste it above

    Drop the HTML into the box and hit “Check Alt Text”. Every <img> tag is analyzed instantly, on your device.

  3. 3Review the issues

    Each image is listed with its problems — missing alt, filename-as-alt, duplicates — plus a concrete fix for each one.

  4. 4Fix and re-check

    Update the alt attributes in your CMS or code, paste the fresh HTML, and run the check again until the score is green.

Why this checker

7 issue types detected

Missing alt, empty alt, filename-as-alt, over-long alt, duplicate alt text, redundant “image of” phrasing, and missing src — all in one pass.

Duplicate alt finder

Spots copy-pasted alt text reused across images, which dilutes both SEO value and the screen-reader experience.

125-character guidance

Flags alt text that most screen readers will truncate, so your descriptions actually get heard in full.

Filename-as-alt detection

Catches alt="IMG_2041.jpg" style mistakes by comparing alt text against the image file name, ignoring case and separators.

Actionable fixes

Every issue ships with a plain-English fix — not just a red flag. Fix, re-paste, and watch the score climb.

Private by design

Parsing happens locally with the browser's DOMParser. Your page source never touches a server.

Frequently asked questions

What is alt text?
Alt text is the alt attribute on an <img> tag. It describes the image for people using screen readers and displays in place of the image if it fails to load. Good alt text is short, specific, and describes what the image shows — not the file name.
Why does alt text matter for SEO?
Search engines cannot “see” images. Descriptive alt text helps your images rank in Google Image Search and gives Google more context about the page topic. Missing alt on important images is one of the most common — and easiest to fix — on-page SEO gaps.
Is empty alt text (alt="") bad?
Not always — it is the correct choice for purely decorative images (dividers, spacers, background flourishes), telling screen readers to skip them. This checker flags empty alt as a warning, not an error: confirm the image is truly decorative, otherwise write a real description.
How long should alt text be?
Aim for under 125 characters. Most screen readers pause or cut off around that length, so anything longer may never be heard in full. Be concise: “Golden retriever catching a frisbee” beats a paragraph.
What is “filename as alt” and why is it flagged?
It means the alt attribute just repeats the file name, like alt="hero-banner.jpg". That helps neither screen-reader users nor search engines. Describe the image content instead: alt="Team celebrating a product launch on stage".
Does this tool upload my HTML anywhere?
No. The analysis runs entirely in your browser using the built-in DOMParser — your page source never leaves the tab. You can even disconnect from the internet after the page loads and it keeps working.
Can I check a live URL instead of pasting HTML?
Not in this version. Browsers block pages from fetching other websites' HTML (a security rule called CORS), so the reliable workflow is: view source on your page, copy, paste here. It takes about ten seconds.

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