Color Contrast Guide: Make Text Easier to Read Before You Publish
Learn how contrast ratios work, what WCAG AA and AAA thresholds mean, and how to review color pairs in real interfaces.
Browser-only utility
Color Contrast Checker, private by default
Compare text and background colors, preview the pair, and review AA and AAA contrast results before publishing interface copy.
Check text contrast
Compare foreground and background colors against common WCAG contrast thresholds before publishing a page, button, or interface state.
Contrast result
Contrast calculated locally in your browser.
16.10:1
Sample heading
This preview shows how readable text may feel with the selected colors.
WCAG checks
AA normal text
Requires 4.5:1
AA large text
Requires 3:1
AAA normal text
Requires 7:1
AAA large text
Requires 4.5:1
UI components
Requires 3:1
Color contrast is calculated locally in your browser. Pasted color values are not uploaded to tempboxs.
How to use contrast checker safely
Why contrast matters
Readable contrast helps people scan pages, complete forms, understand buttons, and use tools in bright, dim, or small-screen contexts. Low contrast can make good content feel broken because the words are technically present but hard to read.
For a utility site, accessible contrast also supports trust. A user checking a password, URL, or email header should not have to fight the interface while trying to make a quick decision.
What the checker measures
The tempboxs Color Contrast Checker calculates relative luminance and contrast ratio for two hex colors. It compares the ratio with common WCAG thresholds for normal text, large text, and user interface components.
Contrast is only one part of accessibility. Font size, weight, spacing, focus states, motion, labels, and context still matter when reviewing a complete design.
- AA normal text threshold: 4.5:1
- AA large text threshold: 3:1
- AAA normal text threshold: 7:1
- AAA large text threshold: 4.5:1
- UI component threshold: 3:1
Practical review workflow
Check the colors used for body text, muted text, buttons, links, inputs, badges, and alert states. If a color pair fails, adjust either the foreground or background until the ratio passes the level your design needs.
After the numbers pass, review the real component on mobile and desktop. Contrast math helps, but actual layout and text size decide whether the interface feels comfortable.
Why people use this tool
Color contrast checks run locally in your browser. tempboxs does not receive pasted color values.
Check WCAG thresholds
Review AA and AAA contrast results for normal text, large text, and interface components.
Preview real color pairs
See sample heading and body text using the selected foreground and background colors.
Copy audit notes
Copy the color pair, ratio, and pass/fail checks into design reviews, issues, or documentation.
Guides from the blog
Learn more about privacy, tracking, passwords, and safer signups.
Word Count and Content Quality: How to Plan Useful Utility Guides
Learn how word count, reading time, headings, examples, and repeated terms can help you plan clearer guides without chasing arbitrary length.
A Privacy and Security Toolkit for Safer Signups
Build a practical browser-only workflow with temporary email, generated passwords, URL cleaning, header review, and tracking-pixel checks.
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FAQ
No. The contrast calculation runs locally in your browser and does not send pasted color values to tempboxs.
This checker supports 3-digit and 6-digit hex colors such as #111, #ffffff, and #00947f.
No. Contrast is important, but accessible design also depends on labels, keyboard support, focus states, text size, spacing, and interaction behavior.
Common WCAG AA guidance for normal text is at least 4.5:1. AAA normal text uses 7:1.