Contrast Check: #FFFFFF on #28A745

White (#FFFFFF) on Success green (#28A745) — 3.13:1, passes AA large.

At a glance

Contrast ratio
3.13:1
WCAG AA (normal text)
Fail
WCAG AA (large text)
Pass
WCAG AAA (normal text)
Fail
UI components / non-text
Pass

White text on a success green background is one of the most frequently checked combinations in web design. The measured WCAG 2.1 contrast ratio is 3.13:1. It passes WCAG AA only for large text (18pt+ or 14pt+ bold), not for body text. White text on green backgrounds is a popular CTA but often skirts the AA boundary.

Frequently asked questions

Is #FFFFFF on #28A745 accessible?
For WCAG 2.1 AA — the most common conformance target — the answer is no for normal-size body text. Normal text needs 4.5:1 and this combination measures 3.13:1. Large text (18pt+ or 14pt+ bold) needs only 3:1, so this combination passes for headings and large UI labels. AAA conformance demands 7:1; this combination falls short of that bar.
Where is this combination commonly used?
Success buttons, confirm modals, "Buy now" actions.
How is this ratio calculated?
WCAG 2.1 contrast ratio is (L1 + 0.05) / (L2 + 0.05) where L1 and L2 are the relative luminances of the lighter and darker colors. Each channel is gamma-corrected (linearized) before applying coefficients 0.2126·R + 0.7152·G + 0.0722·B. The two formulas weight green most because the human eye is most sensitive to green wavelengths.
What if I need a higher ratio than 3.13:1?
Adjust either the foreground or background lightness in the calculator above. The Suggestions panel automatically computes the nearest passing color in each direction (lighter or darker) for AA and AAA targets.

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