contrast?bg=string&fg=string

WCAG contrast ratio calculator, accessibility checker, color contrast, a11y, WCAG 2.1 AA AAA, text contrast, color blindness, readable text color.

WCAG contrast ratio calculator, accessibility checker, color contrast, a11y, WCAG 2.1 AA AAA, text contrast, color blindness, readable text color. Calculate WCAG 2.1 contrast ratio between two colors and return pass/fail for AA/AAA at normal/large text sizes. Accepts payment on Base or Solana — either network works.

UNRATEDListedProse in the URL

Overview

Grade?

UNRATED

0 of 30 paid calls toward a letter

Price

$0.008 per call

Paid calls

none yet

delivery unknown until someone pays

More info

Seller?

0x4466d4a8…d6dd125e

URL

https://api.x402node.dev/color/contrast?bg=string&fg=string

Seen

first 35 days ago · last 4 days ago

63 free handshakes

Payment

Pays through

x402

Offered on?

Base USDC, Solana

Listed on?

Base, Solana

Score, from free handshakes onlyweights 2026.09.6

UN
RATED

0.733 liveness verified, no letter

To a letter · 30 paid calls

0 of 30

Held back by sample size, not by the seller · gap to 1.000 is 0.267: 0.142 uncertain ? + 0.125 short ? · 0.067 to B

How the composite of 0.733 is made up, part by part
Component	Weight	Measured	Lower bound ?		Adds	Short ?	Uncertain ?
latency p95costs the most it answered as fast as its class	0.20	0.38	0.000		0.000	−0.125	−0.075
liveness it answered at all	0.60	1.00	0.888		0.533	0	−0.067
price stability the price stayed where it was listed	0.20	1.00	1.000		0.200	0	0
Composite	1.00		0.733	gap to 1.000 = 0.267 · 0.125 short · 0.142 uncertain	0.733	−0.125	−0.142

Not measured: correctness · nobody paid; honesty · nobody paid; schema conformance · no answer had a published shape to check

The multiplication, written out

  0.200 × 0.000   latency p95    
+ 0.600 × 0.888   liveness       
+ 0.200 × 1.000   price stability
= 0.733           → UNRATED: 55 of 30 paid calls      weights 2026.09.6 · 55 samples · seed cap_01M1A5QKQK6BP9NQ6ARXDZ313A|2026-09-04T09:47:15.848Z|2026.09.6

Verify it yourselfnpx teppi-check https://api.x402node.dev/color/contrast?bg=string&fg=stringcurl -s https://api.teppi.xyz/v1/trust/cap_01M1A5QKQK6BP9NQ6ARXDZ313A