Alt text generator for your photos

Alt text is read aloud by screen readers to people who can’t see the photo. Instagram already writes automatic alt text with object recognition, which tends to come out as a list of things in the picture. What you write replaces it, so say what matters for the post, not every object in view.

• Start with the subject: “A bottle of rose face serum held up in a bathroom”, not “Image of a bottle”. Screen readers already announce that it’s an image.
• Put the words from a quote card, menu, poster or screenshot in full. Someone who can’t see the photo can’t read it either.
• Name what only you know: the product, the place, the person (if they’re happy to be named), the dish.
• Keep it to a sentence or two. Save colours, layout and mood for the longer description, or for the caption.
• Leave out hashtags, emoji and “click the link”. They get read out letter by letter or make no sense out loud.

Tip: Carousels need alt text on every photo. Instagram asks for it slide by slide, so the generator keeps one box per photo in the order you added them.

In the Instagram app (iPhone and Android), you can add it while posting or change it later. This is how Instagram’s Help Center article “Edit the alternative text for a post on Instagram” describes it. The article adds that the text is only read aloud if someone is using a screen reader:

1. New post: choose your photo, tap Next, pick a filter and edit, then tap Next again.
2. Tap More options, then Write alt text.
3. Paste or type your alt text and tap Done, then share the post.
4. Post that’s already up: open it, tap the three dots (Options), tap Edit, then Edit alt text in the bottom right. Save with Done.

On a computer, the setting sits under Accessibility in the last step before you share, and under Edit, then Accessibility, for a post that’s already live.

Facebook writes its own alt text too, starting with “Image may contain:”. The Facebook Help Centre article “Edit the alternative text for a photo on Facebook” says the app only lets you edit it after the photo is posted, and that to see and edit it before you post you should log in to Facebook on a computer.

1. Computer, before posting: click Photo/Video, choose the photo, hover over it and click Edit, then Alternative text in the menu on the left.
2. Click Custom alt text, write yours in the box and click Save.
3. App, after posting: tap the photo, tap Options in the top right, then Edit alt text.
4. On an iPhone, tap Override generated alt text first. Type yours and tap Save.

Florence-2 base is a small model, which is why it fits in a browser. In our tests it described a hand holding a serum bottle well, called a toothbrush “two toothbrushes” and invented a headband. It writes in English only, and it reads printed Latin-alphabet text, not handwriting or scripts like Devanagari.

The first run downloads the model once: about 360 MB where the browser’s WebGPU supports half-precision maths (current Chrome, Edge and Safari on most devices), or 230 MB for the slower WebAssembly version elsewhere. After that it starts straight away. With WebGPU a photo takes a few seconds; without it, about half a minute.