Is this font size tester free?

Yes, completely free with no signup and no usage limits.

Does my data leave my device?

No. All processing runs entirely in your browser. Nothing is sent to any server.

Yes. Works on iPhone Safari and Android Chrome without installing any app.

Font Size Tester

Preview your text at different font sizes and line heights to check readability for all users.

100% client-side · no upload

Preview text

Font size: 16px

Line height: 1.5

Font weight

Enter your sample text in the text area above.
Drag the sliders to adjust font size and line height and see the live preview update.
Check the WCAG compliance badges: body text should be at least 16px, and large text at least 18px (or 14px bold).

Is this font size tester free?: Yes, completely free with no signup and no usage limits.
Does my data leave my device?: No. All processing runs entirely in your browser. Nothing is sent to any server.
Does it work on mobile?: Yes. Works on iPhone Safari and Android Chrome without installing any app.