AI alt text generator
Describe what the image shows and the AI returns 3 alt text options: concise, descriptive and with your keyword in the right dose. No sign up.
How to write the perfect alt text
The alt text (alternative text) is the description you attach to an image in the HTML "alt" attribute. Screen readers read it aloud for blind or low-vision people, it shows in place of the image when it fails to load, and it helps Google understand what the image shows. Good alt text serves two causes at once: accessibility and image SEO.
Why alt text matters for accessibility and SEO
For accessibility, alt text is the only way a screen reader user learns what is in the image. For SEO, it is the main signal Google uses to understand and rank the image in search and Google Images. The same line of text solves both problems, so it is worth writing with care.
- Screen readers read the alt aloud, giving the image content to people who cannot see it.
- Visual fallback: the text shows when the image fails to load on a bad connection or broken link.
- Google Images: the alt helps the image rank and bring traffic from image search.
- Page context: it tells the search engine what the image adds around the text.
The ideal alt text length
Aim for around 125 characters or less. That is the point where most screen readers read the text without cutting it and where the description stays complete without dragging. Describe the meaningful content of the image, not every detail, and stop when the sentence already says what matters.
| Attribute | Recommended | Why |
|---|---|---|
| Length | Up to 125 characters | Limit most screen readers read without cutting |
| Opening words | No “image of” or “photo of” | The screen reader already announces it is an image |
| Keyword | Once, naturally | Helps SEO without turning into spam |
| Decorative image | Empty alt (alt="") | Lets the screen reader skip what carries no information |
Best practices for writing alt text
- Describe the meaningful content of the image, focused on what it communicates on the page.
- Be concise: aim for up to 125 characters and cut anything redundant.
- Do not start with “image of” or “photo of”, since the screen reader already says it is an image.
- Use the keyword sparingly: only when it truly describes the image, and only once.
- Purely decorative images take an empty alt so the screen reader ignores them.
Does the tool read the image or do I describe it?
You describe in text what the image shows and the AI turns that description into clean alt text, at the right length and with the keyword well placed. So the generation is fast, free and works for any image, even ones not published yet.
Common alt text mistakes
- Leaving the file name (DSC_0231.jpg) in place of a real description.
- Stuffing keywords, which hurts accessibility and SEO at the same time.
- Leaving the alt empty on images that carry important information.
- Writing a long paragraph that drags for screen reader users.
Alt text questions
Is the generator free?
Yes, it is free and needs no sign up. Describe what the image shows and get 3 alt text options instantly.
What is alt text?
It is the alternative text of an image, written in the HTML alt attribute. It describes the image for screen readers and for Google.
Does the tool need the image?
No. You describe in text what the image shows and the AI writes the alt text from that description.
What is the ideal length?
Aim for around 125 characters. That is the point where most screen readers read the text without cutting it.
Do I need to use the keyword?
Only when it truly describes the image, and only once. Repeating the keyword hurts both accessibility and SEO.
Does every image need alt text?
Images that carry information do. Purely decorative images should have an empty alt so the screen reader skips them.
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