Contrast Checker
Check whether a text and background colour pair meets WCAG accessibility contrast rules. Pick two colours and see the ratio plus AA/AAA pass or fail for normal and large text.
HELLO WORLD, THIS IS TOOLVERSE
hello world, this is toolverse
Hello World, This Is Toolverse
Hello world, this is toolverse
helloWorldThisIsToolverse
HelloWorldThisIsToolverse
hello_world_this_is_toolverse
hello-world-this-is-toolverse
HELLO_WORLD_THIS_IS_TOOLVERSE
hElLo WoRlD, tHiS iS tOoLvErSe
How to use it
Colour contrast is the difference in brightness between text and its background, expressed as a ratio from 1:1 (identical) to 21:1 (black on white). The Web Content Accessibility Guidelines (WCAG) set minimum ratios so that people with low vision can read your text. This tool computes the ratio from each colour's relative luminance and checks it against the WCAG thresholds. WCAG level AA requires 4.5:1 for normal text and 3:1 for large text (about 18.66px bold or 24px and up). The stricter AAA level requires 7:1 and 4.5:1. Aim for AA as a baseline and AAA where you can.
Frequently asked questions
- What is the difference between camelCase and PascalCase?
- Both join words without spaces; camelCase starts with a lowercase letter (myVariable), while PascalCase capitalizes the first letter too (MyVariable).
- Is my text uploaded anywhere?
- No. All conversions happen in your browser — your text is never sent to a server.
- What's the difference between title case and sentence case?
- Title case capitalizes the first letter of every word; sentence case capitalizes only the first letter of each sentence.
- Does converting case change my original text?
- No — the tool never modifies what you typed. Your input stays exactly as entered in the text box; each of the ten result cards shows a separate converted copy generated fresh from that input. You can switch between results, keep editing your original text, and copy any converted version without losing or altering the source.