This alt text generator writes a suggested description from three short answers you give it: what the image does on the page, what it shows, and which detail matters. It then hands you the finished HTML, flags phrases like "image of", warns when the text runs long, and outputs an empty alt for decorative images.
It does not look at your picture. That is on purpose. Software that tries to describe a photo by itself can only guess, while you already know why the image is on the page, and that knowledge is what good alt text is built on. This tool turns your knowledge into well formed text quickly, which is useful when you have a batch of images to describe.
Quick facts
Cost and sign up
Free, nothing to install, no accountYou enter
Image role, subject, important detail, page contextYou get
Suggested alt text and a readyimgtagImage roles
Informative photo, link or button, decorative, image of text, chart or diagramChecks
Length warning and a flag for "image of" and "picture of"Looks at the image
No. You describe it; the tool shapes the words
How to use the alt text generator
The generator sits just above this text. It starts with one question, and the fields below it change to suit your answer.
- What does the image do on the page? Pick one of five roles: informative photo or picture, link or button, decorative only, image of text, or chart, graph or diagram. This is the choice that matters most, because a linked logo and a product photo need completely different words.
- Fill the fields that appear. For a photo you get "Main subject", "Important detail" and an optional "Why it is on this page". A link or button asks where it goes or what it does. An image of text asks for the exact words. A chart asks what it shows and the main takeaway.
- Read the suggestion. It updates as you type, together with a sample
imgtag. - Act on the notes. The tool strips a leading "image of" and tells you it did, warns past 125 characters, flags file names and points out text typed in all capitals, which some screen readers spell letter by letter.
- Copy. Use "Copy alt text" for an editor's alt field, or "Copy HTML" and swap the placeholder file name for yours.
Choose decorative only and the fields disappear: you get alt="", which tells screen readers to skip the image. Choose chart and the tool reminds you to put the full numbers in a table or nearby text.
Not sure which role fits? The decision guide on our alt text basics page walks through it in five questions.
Two worked examples
Example 1: a product photo in an online store
You sell a handmade mug. The photo shows it from the side on a wooden table.
- Role: informative photo or picture
- Main subject: ceramic coffee mug
- Important detail: with a matte green glaze and speckled rim
- Why it is on this page: product page, buyers compare glazes
The tool joins the subject and detail and adds a full stop:
<img src="your-image.jpg" alt="Ceramic coffee mug with a matte green glaze and speckled rim.">The wooden table is left out because it does not help a shopper decide. If size matters, add it to the detail field.
Example 2: a logo that links to the home page
- Role: link or button
- Where the link goes: Riverside Bakery home page
Here the look of the logo does not matter at all. The tool reminds you to describe the destination, and the result is:
<a href="/"><img src="your-image.jpg" alt="Riverside Bakery home page"></a>(The link wrapper is yours to add; the tool gives you the img tag.) A screen reader user hears "link, Riverside Bakery home page", which is exactly what they need. Writing "round blue logo with a wheat sheaf" would describe the picture but not say where the link leads.
What automatic alt text gets wrong
Many apps and plugins now offer automatic alt text: software that guesses a description from the pixels. It is better than nothing for a photo that has no alt at all, but audits show the same problems again and again.
| Problem | Typical automatic result | What a person would write |
|---|---|---|
| No idea of purpose | "A drawing of a house" | "Home page" (the image is a link) |
| No page context | "A person holding a phone" | "Customer scanning the QR code at our checkout counter" |
| Text in the image missed or garbled | "A sign with text" | "Closed on Mondays" |
| Guesses about people | Guessed age, gender or mood | Only what is visible and relevant, such as "Speaker at the podium" |
| Charts reduced to shapes | "A chart with blue bars" | "Bar chart: sign ups rose every quarter, from 120 to 410" |
| Decorative images described | "Abstract pattern of lines" | Empty alt, so it is skipped |
| Confident but wrong | "A dog on a beach" for a cat on sand | The correct subject |
The root issue is simple: the right words come from the image's purpose on the page, and purpose is something pixels cannot reveal.
Why a person should check every description
Whether a suggestion comes from this tool, a plugin or a phone feature, someone who knows the page should read it before it goes live. Ask three questions:
- Is it accurate? Wrong alt text is worse than short alt text, because the listener has no way to notice the mistake.
- Does it fit the page? A jacket shot on a fashion page needs color and cut; the same photo on a weather blog may just need "Person in a rain jacket".
- Is it the right length? One or two short sentences. Long text belongs in the page body.
Never let a tool describe people's identity, ethnicity, disability or emotions by guessing. Describe what is visible and relevant, and name people only if the page itself does.
The W3C images tutorial sets out the principles auditors apply. Our alt text writing method turns them into steps; compare your result with the before and after pairs in alt text examples.
Bulk generators, plugins and browser extensions
Plugins for site builders and online store platforms can fill in alt text for hundreds of images at once. Browser extensions can suggest a description when you right click an image. These save time on a large backlog, but treat their output as a first draft:
- Run the bulk fill only on images that have no alt at all, so you never overwrite text someone wrote with care.
- Review the most visited pages and key journeys first: home, product pages, checkout, sign up.
- Mark purely decorative images as decorative instead of keeping a guessed description.
- Fix linked images and icon buttons by hand, since bulk tools rarely know their destination.
- Spot check the rest with our alt text checker to catch file names and repeated text.
Word processors and slide apps also offer automatic descriptions, usually with a note that they were generated. Edit them the same way, or tick "Mark as decorative" where it applies. Our guide to adding alt text shows where those fields are.
Alt text for Instagram and other social posts
Social apps describe photos automatically too, and on Instagram the result is often as vague as "May be an image of 2 people and text". You can write your own: when posting, open Advanced settings on the caption screen and choose Write alt text. Menu names move around between app versions, so look for the Accessibility area if you cannot find it.
The generator works well for this. Choose "informative photo", put the subject and the detail your followers would notice, and copy only the text. Our Instagram alt text guide covers editing older posts.
People sometimes search for alt text that boosts likes. Alt text does not change how a post is ranked for likes; its job is to let blind and low vision followers enjoy the post. Keep it honest and skip hashtags.
Generator results compared with writing from scratch
The tool is a shortcut, not a replacement for judgement. It helps most when you know what to say but want consistent, well formed output, such as when a team of editors handles many images. It cannot know whether an image is a duplicate of nearby text, whether a chart's numbers are correct, or whether the photo shows the right product.
Search engines read the same alt attribute, so a clear human description also helps image search. Read alt text for SEO before adding keywords, because stuffing them in harms both listeners and rankings.
Questions people ask
Is this alt text generator free?
Yes. It runs entirely in your browser, needs no account and has no usage limit. Your answers stay on your device and vanish when you leave the page.
Can it generate alt text for images I upload?
No. It does not look at the picture at all. You tell it the role, subject and key detail, and it shapes those into alt text and HTML. This keeps the description tied to why the image is on your page.
Is automatic alt text good enough for accessibility?
Usually not on its own. Software that guesses a description cannot know the image's purpose, often misses or misreads text, and sometimes gets the subject wrong. Use it as a draft and have a person review every result.
Is there a bulk alt text generator?
Plugins for site builders and store platforms can fill many images at once. Use them only on images with no alt, review key pages by hand, and mark decorative images as decorative rather than keeping a guessed description.
Is there an Instagram alt text generator?
Instagram adds its own automatic descriptions, but they are often vague. You can use this tool to draft a better one and paste it into the Write alt text field, which Instagram keeps among the advanced options of a new post.
What does the generator do for decorative images?
It outputs an empty alt attribute, alt with nothing between the quotes. That tells screen readers to skip the image, which is the correct result for pure decoration.