What Is Alt Text?
Alt text is the short description inside an image's alt attribute. Screen readers read it aloud, browsers show it when an image fails to load, and search engines use it to understand what the image shows.
Good alt text makes your pages more accessible and helps your images appear in Google Images.
How to Use This Alt Text Checker
- Copy your page HTML. In Chrome press Ctrl + U, then select all and copy. Pasting just your article HTML also works.
- Paste it into the box. Every image is listed with its file name and alt text.
- Fix anything marked red or orange. The status column explains exactly what is wrong.
What the Checker Flags
| Issue | Why It Matters |
|---|---|
| Missing alt attribute | Screen readers may read out the file name instead |
| Empty alt | Correct for decorative images, a problem for meaningful ones |
| File name as alt | "IMG_4021.jpg" tells nobody what the image shows |
| Starts with "image of" | Screen readers already announce it as an image |
| Over 125 characters | Hard to listen to, and often keyword stuffed |
| Duplicate alt text | Different images usually deserve different descriptions |
How to Write Better Alt Text
- Describe the image as you would to someone on the phone.
- Be specific: "Bar chart of monthly organic traffic rising from 2,000 to 9,000" beats "chart".
- Use a keyword only when it genuinely describes the image.
- Leave alt empty for purely decorative images like dividers and background shapes.
For the full picture on image SEO, read how to optimize images for SEO, lazy loading images explained, and WebP vs AVIF. To check headings on the same page, try the heading structure checker.
Frequently Asked Questions
1Does alt text help SEO?
Yes. Google uses alt text, along with the page content and file name, to understand images. Descriptive alt text helps images rank in Google Images and makes the page more accessible.
2How long should alt text be?
Keep it concise, usually under 125 characters. Describe what matters in the image without stuffing keywords.
3When should alt text be empty?
Use an empty alt attribute for purely decorative images such as dividers, spacers or background shapes, so screen readers skip them.
4Does this alt text checker upload my HTML?
No. The alt text checker works entirely in your browser and never uploads or stores what you paste.