WCAG contrast ratio

Client

WCAG 2.x contrast formula.

Contrast ratio between two #RRGGBB colors.

About WCAG contrast ratio

Contrast ratio between two #RRGGBB colors. The interactive transform on this page runs in your browser tab—Toolcore does not need your paste for the core operation described above.

How to use this page

Paste or type in the main workspace, run the primary action from the toolbar, then copy or download the result. Use Load example when the page offers it, or URL prefill (?q= / ?qb=) so agents and tickets open the same input.

Contrast 21.00:1 (AA normal text OK)

Common use cases

  • WCAG contrast ratio for quick local checks without uploading data.
  • Copy results into tickets, docs, or classroom notes.

Common mistakes to avoid

  • Unexpected input shape

    See the intro and how-to notes for accepted formats.

FAQ

Is processing local?

Yes—this runs entirely in your browser.

Agent prefill?

Use q or qb for the main text field when supported.

More tools

Related utilities you can open in another tab—mostly client-side.