Image Alt Text Generator
Image & Video Tools
Generate accessible, descriptive alt text for any image in seconds. Free, browser-based, no signup — better accessibility and SEO.
Image Alt Text Generator
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What alt text actually does
Alt text is the written description a screen reader speaks aloud when it reaches an image, and what search engines and browsers fall back to when a picture fails to load. It lives in the HTML alt attribute, so it is invisible on the page unless something breaks. There is no hard character cap, but most screen readers and the WCAG guidance favour roughly 125 characters or fewer before listeners tune out. The insight most people miss: decorative images that add no information should get empty alt text (alt=""), not a description, so screen readers skip them entirely.
Alt text tips
- Describe what matters in context, not every pixel; a recipe photo needs the dish named, not the lighting.
- Skip "image of" or "photo of" since screen readers already announce that an image is present.
- Keep it near 125 characters; longer descriptions get cut or fatigue listeners, so move detail into surrounding text.
- Use empty alt (alt="") for purely decorative images so assistive tech skips them instead of reading filler.
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Image Alt Text Generator — common questions
Latest questions readers ask us about this topic.
How long should alt text be?
There is no strict limit in HTML, but aim for about 125 characters or fewer. Some screen readers truncate longer strings, and concise descriptions read better aloud. For complex images, use a short alt plus a longer caption or nearby text.
What is the difference between alt text and a caption?
Alt text lives in the HTML alt attribute and is read only by screen readers or shown when an image fails to load. A caption is visible to everyone, sits below the image, and adds context. They serve different audiences and should not duplicate each other.
Do images need alt text for SEO?
Yes. Search engines cannot see images, so alt text helps them understand and rank your content, and it powers image search results. It is also a core WCAG accessibility requirement, so good alt text serves both ranking and real users at once.
Related questions
The sub-questions readers ask next — answered, with where to go.
Specificity and tension. A scroll-stopping opener promises a concrete payoff ('the 3-word edit that doubled my reply rate') or opens a loop the reader needs closed — not a vague 'let's talk about engagement'. Front-load it: on most feeds only the first line shows before a cut-off, so the hook has to do its work there. Test several angles for the same post; the winner is rarely the one you'd have guessed.
Style your opening lineMatch the length to the job, then check it against the limit. Instagram captions can run long for storytelling but the hook must land in the first ~125 characters before 'more'; X/Twitter rewards tight, standalone lines; LinkedIn truncates around two lines. TikTok and Reels captions are short by nature. The reliable move is to draft freely, then trim against a live counter so nothing important gets cut.
Check the limit liveFewer, and more relevant, than the old advice. The era of 30 generic tags is over — most platforms now reward a small set (roughly 3–8) that genuinely describe the post, mixing one or two broad tags with several specific, lower-competition ones. Stuffing tags reads as spammy and can suppress reach. Put them where they don't interrupt the read: end of the caption or first comment.
Read the content hubTreat the bio as a one-line pitch, not a résumé. Open with who you help and the outcome they get, add a single proof point, and close with a reason to follow or a clear next step. Keep it skimmable, lead with the words people would search, and reserve any styled text for one emphasised phrase. Links and @mentions stay plain so they stay clickable.
Generate a bioExplore the topic cluster
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