Color Contrast Checker
Check foreground and background color contrast before shipping UI text and controls.
This tool runs in your browser. Inputs stay local and are not sent to any server.
How to use this result
Contrast checking prevents beautiful but unreadable design decisions, especially on mobile screens.
Examples
Dark text
Common questions
Q.Is contrast the only accessibility requirement?
No. It is one important baseline along with size, focus states, semantics, and interaction design.
Before using Contrast
When it helps
Contrast is useful when small but frequent calculations or transformations need to be handled without opening a heavy application. It is designed for situations like turning #181514 on #f3efe7 into Readable high-contrast pairing without leaving the browser workflow.
Suggested workflow
The basic workflow is simple: enter Foreground and background, adjust options when needed, and review Contrast ratio. Before relying on the result, check the units, date, file type, rounding basis, or other assumptions that may change the outcome.
How to verify results
Contrast is a supporting utility for quick judgment. If the result affects contracts, filings, payments, security, customer data, or other important decisions, verify it against official sources, source systems, internal policy, or qualified review.
Data handling notice
Browser-local processing: the main calculation or conversion runs in your browser.
No server storage: except for UI preferences such as favorites, ZHS does not store your input files or text on the server.
Sensitive-data caution: even with local processing, avoid entering production secrets, national IDs, financial data, or raw customer data into public web tools.