What is alt text and why does it matter?

Alt text (alternative text) is a written description of an image, set via the HTML `alt` attribute. It serves three purposes: (1) screen readers announce it to blind and low-vision users, (2) it appears when the image fails to load, and (3) search engines use it to understand image content for ranking and image-search indexing. Good alt text is required for WCAG 2.2 compliance (Success Criterion 1.1.1) and helps you rank in Google Image search.

How long should alt text be?

Keep alt text under 125 characters. Most screen readers truncate at that length. The InsiteChat AI Alt Text Generator produces three variants per request: a recommended length, a shorter version under 80 characters for tight spaces, and a longer version up to the 125-character limit when you need more context.

When should alt text be empty (alt="")?

Use empty alt text (alt="") for purely decorative images that add no information — background patterns, decorative dividers, icons that repeat adjacent text. Screen readers will skip them, which is the correct behavior. Missing the alt attribute entirely is different and triggers WCAG failures; always include alt="" rather than omitting it.

Should I include keywords in alt text for SEO?

Include your target keyword only when it accurately describes the image. Keyword-stuffing alt text hurts both accessibility (screen reader users hear nonsense) and SEO (Google detects unnatural alt text and discounts it). The AI Alt Text Generator naturally weaves in the page keyword when you provide one — but only if it fits the image content.

Does this tool actually look at the image?

Today the AI generates alt text from your written description of the image, not from the image file itself. This keeps the tool fast and free with no upload required. You describe what is in the image — people, action, setting — and the AI produces accessibility-compliant alt text. Image-recognition input is planned for a future version.

Is this tool really free?

Yes. The AI Alt Text Generator is completely free, no signup required, no rate limits beyond standard abuse protection. It is part of InsiteChat's suite of free AI and SEO tools, including the AI Readiness Grader, LLM-Friendly Website Score, and AEO Score.

Free Tool

AI Alt Text Generator

Generate WCAG-compliant, SEO-friendly alt text for any image in seconds. Under 125 characters, screen-reader ready, with shorter and longer variants.

Describe the image

Be specific about people, action, setting, and mood. Avoid “image of” or “picture of”.

Page topic or keyword (optional)

Only used if it actually fits the image. The AI will not keyword-stuff.

What is alt text?

Alt text (alternative text) is a written description of an image, set via the HTML alt attribute. It serves three purposes at once:

Accessibility — screen readers announce alt text to blind and low-vision users so they understand what each image conveys.
Fallback — alt text appears when an image fails to load (slow connection, broken URL, content-blocker stripping the image).
SEO — search engines use alt text to understand image content for ranking and for Google Image search.

Missing alt text is one of the most common WCAG 2.2 failures (Success Criterion 1.1.1 “Non-text Content”). It is also a top reason images don’t rank in image search.

Best practices for writing alt text

Keep it under 125 characters. Most screen readers cut off after that, and long alt text becomes tiring to listen to.
Describe what is visually significant— people, actions, setting, mood. Skip redundant openers like “image of” or “picture of” — screen readers already announce that it’s an image.
Use empty alt (alt="") for decorative images. Background patterns, icons that repeat adjacent text, and pure aesthetic flourishes should have empty alt so screen readers skip them. Never omit the attribute entirely.
Include keywords only if they fit.If your page targets “Bangalore cafe” and the image shows a barista at a Bangalore cafe, weaving that in is natural. Forcing the keyword in just for SEO hurts both accessibility and ranking.
Match the surrounding tone. Formal page → formal alt text. Casual blog → conversational alt text.

How this AI alt text generator works

Describe what is in your image, optionally add the page topic or target keyword, and the AI produces three alt-text variants:

Recommended — the best balance of descriptiveness and brevity, under 125 characters.
Shorter — under 80 characters for tight layouts or social media OG tags.
Longer — up to the 125-character limit when you need to capture more context (data visualizations, complex scenes, charts).

Today the AI generates alt text from your written description, not from the image file itself — no upload required, no privacy concern. Vision-input is on the roadmap.