Alt text generator: a description of your image to start from.

Enter the URL of a public JPEG, PNG, GIF or WebP image. Our server fetches it and a model describes what it shows. You get suggested alt text to edit so it fits the page and the reason the image is there.

By · Updated September 25, 2026

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Alt text generator

Runs on our server, which fetches the image URL you enter and sends the image to Anthropic's Claude. We count runs and never save what you enter; an identical request may be answered from memory for up to five minutes.

A public link to a JPEG, PNG, GIF or WebP file.

What you can do with it

  • Write alt text for a batch of product or blog images you never described
  • Get a first description of a chart or screenshot to tighten by hand
  • Check what a model actually sees in an image before you rely on it
  • Fill in missing alt attributes flagged by an accessibility audit

How it works, step by step

  1. 1

    Decide whether the image carries information

    If the image is decorative, such as a background texture, a divider or an icon next to text that already says the same thing, give it an empty alt attribute (alt="") so screen readers skip it. Only images that add information need a description.

  2. 2

    Ask why the image is on this page

    The same photo needs different alt text in different places. On a recipe page, the dish; on a kitchen-design page, the countertop. Describe what matters in that context.

  3. 3

    Describe, briefly, without saying it is an image

    Screen readers already announce an image, so skip image of and picture of. Say what it shows in a short phrase or sentence. If a chart or diagram has key data, summarize the takeaway and put the detail in the page text.

  4. 4

    Include a keyword only if it is true

    If the page's topic word honestly describes the image, it can appear naturally. Do not add keywords the image does not show. Alt text is for people who cannot see the image first.

  5. 5

    Check it in place

    Read the alt text with the surrounding paragraph. It should add to the text, not repeat the caption word for word.

Alt text is for people first

Alt text is the text alternative for an image. A screen reader reads it aloud, a browser shows it when the image fails to load, and search engines use it to understand what the image depicts. Of those three, the first is the reason it exists. If you write alt text for someone who cannot see the image, you will almost always write good alt text for search as well.

That changes the question from “what keywords go here” to “what would someone miss if they could not see this?”

Context decides what to say

The same image can need different alt text on different pages. A photo of a person at a laptop in a café might be “Founder Ana Ruiz working at a café table” on an about page and “Laptop showing the invoice screen” on a product page. Neither is wrong. Each describes what matters in that place.

This is the main limit of any generator, this one included. The model sees the image. It does not see your page, your caption or why you chose the image, so it describes the image in general. Your job is to cut that general description down to the part that fits.

Rules of thumb

  • Skip “image of” or “photo of”. Screen readers already announce it. Say “screenshot” or “illustration” only if the format matters.
  • Be concise. A short phrase or a sentence is usually enough. If an image needs a paragraph, put that in the page text or a caption.
  • Decorative images get empty alt. Use alt="" for purely visual elements. Leaving the attribute out is not the same; some screen readers then read the file name.
  • Text in images should be in the alt. If the image contains words that matter, such as a sign or a slide title, include them.
  • Charts need the takeaway. Say what the chart shows (“Monthly signups doubled between March and June”) and put the full data in the page.
  • Keywords only if true. Use the page’s topic word if it honestly describes the image. Stuffing keywords into alt text helps nobody and reads badly aloud.

Checking a whole page

To see whether a page’s images have alt attributes at all, alongside the rest of its metadata, the website metadata checker reads a URL’s HTML. Fixing alt text is part of making a page readable by everything that visits it, people and crawlers alike. The free AI-readiness check looks at the rest of that picture for a whole domain.

AltoRank plans and drafts SEO content for a site every week, and a person approves each piece before it publishes.

Frequently asked questions

Can I paste the generated alt text straight in?

Use it as a draft. The model sees the image but not the page it sits on, so it cannot know which detail matters to your reader. Edit it to describe what is relevant in context, and shorten it if it reads like an inventory.

Does alt text help SEO?

Google uses alt text, along with the surrounding content, to understand what an image shows, which matters for image search. But its first job is accessibility: it is what a screen reader user hears. Write it for them and it will serve search too.

Should every image have alt text?

Every image should have an alt attribute, but decorative images should have an empty one (alt=""). That tells assistive technology to skip them. A missing alt attribute is different: some screen readers then read out the file name.

What image types and links work?

A public link to a JPEG, PNG, GIF or WebP file. The URL must be reachable without a login; images behind authentication or blocked from outside requests cannot be fetched.

What happens to the image I submit?

Our server fetches the image from the URL you enter and sends it to Anthropic's Claude, a fast model, which writes the description. We count how many times the tool runs and never save what you enter; an identical request may be answered from memory for up to five minutes. There is a daily usage limit so the tool can stay free without a signup.

More free tools

Free Website Metadata Checker: Title, OG, Schema Enter a URL and see the page's title, meta description, canonical, robots tag, Open Graph and Twitter tags, JSON-LD types, h1 and language. SEO Health Check: The Agency Audit Checklist A repeatable SEO health check: crawl, indexation, structure and AI-readiness, in problem-finding order. Free AI Crawler Simulator: See What GPTBot Sees Fetch any URL as GPTBot, ClaudeBot, PerplexityBot, OAI-SearchBot and Googlebot. See each robots.txt verdict, status code and the text in the raw HTML. Free FAQ Schema Generator (JSON-LD, Article, Breadcrumb) Generate valid Article, FAQPage and BreadcrumbList JSON-LD, and the one rule that keeps it from backfiring.
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