Contrast ratio
Calculate the numeric contrast ratio between text and background colors.
Free. Private. No uploads.
Contrast Checker
Check whether text and background colors have enough contrast for readable interfaces. Pocket Dev calculates the ratio locally and shows pass or fail guidance.
What it does
Check color contrast before shipping a UI.
Contrast Checker helps developers and designers verify readability for websites, dashboards, mobile apps and design systems. Pick text and background colors, choose font size and weight, then review the contrast result.
Pass and fail labels
See practical pass or fail guidance for normal and large text.
Readable UI preview
Preview the color pair before using it in a component or style guide.
How to use
Use Contrast Checker in a few steps.
- Open the Contrast Checker tool inside Pocket Dev.
- Choose text and background colors.
- Set font size and weight.
- Review the WCAG contrast result before using the colors.
FAQ
Contrast Checker questions
Is this contrast checker free?
Yes. Pocket Tools is free to use.
Does it check WCAG contrast?
Yes. It calculates contrast ratio and shows pass or fail guidance for text sizes.
Can I use it for mobile app colors?
Yes. The same readability checks are useful for web and mobile UI colors.