# Alt Text Checker

> Find images with missing, empty, filename-based or overlong alternative text.

Alt text fails in predictable ways: a missing attribute, an empty one on a meaningful image, the filename copied in, a redundant "image of" prefix, or a description so long that screen readers truncate it. This checker finds all five in pasted HTML and explains what each image needs instead.

**URL:** https://convertto.tech/t/alt-text-checker
**Category:** Accessibility (https://convertto.tech/c/accessibility-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Checks:** Missing, wrongly empty, filename-as-alt, redundant prefix and overlong descriptions
- **WCAG criterion:** 1.1.1 Non-text Content, Level A
- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your html.
2. Set the flag alt text longer than.
3. The result appears immediately — copy or download it.

## FAQ

### When should alt text be empty?

When the image adds nothing a listener would miss — a decorative divider, a background flourish, or an icon beside text that already says the same thing. Use alt="" with role="presentation" so screen readers skip it entirely, rather than omitting the attribute.

### How long should alt text be?

One clear sentence is usually right. Some screen readers truncate around 125 characters, so if a description genuinely needs more, put it in the surrounding text where every reader benefits.

## Related tools

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- [ARIA Roles Reference](https://convertto.tech/t/aria-roles-reference): Search ARIA roles with their required attributes, native HTML equivalents and gotchas.
- [HTML Landmark Checker](https://convertto.tech/t/html-landmark-checker): Check a page for the landmark regions screen reader users navigate by.
- [Link Text Checker](https://convertto.tech/t/link-text-checker): Find vague link wording — "click here", "read more", bare URLs and duplicated labels.
- [Palette Accessibility Grader](https://convertto.tech/t/palette-accessibility-grader): Grade every colour in a palette against one or more backgrounds for WCAG contrast.
- [AI Alt Text Generator](https://convertto.tech/t/ai-alt-text-generator): Describe an image with a captioning model running in your browser — a first draft for the alt attribute you then edit.
- [Touch Target Size Checker](https://convertto.tech/t/touch-target-checker): Check whether a button or link meets the minimum tap target size and spacing.
- [WCAG Contrast Checker](https://convertto.tech/t/contrast-checker): Check colour contrast against WCAG AA and AAA thresholds for accessible text.