$0.001
per call · USD Coin on Base
Colour utilities: ?op=convert (default) turns any hex/rgb()/hsl()/CSS-name into hex, rgb, hsl, hsv, alpha, relative luminance and exact CSS name; ?op=contrast with ?fg=&bg= returns the WCAG 2.x contrast ratio and AA/AAA pass/fail for normal & large text plus UI components (accessibility / EAA); ?op=palette derives complementary, analogous, triadic, tints and shades. Send hex without '#'.
Endpoint
GET https://402utils.com/v1/color4
Calls / 30d
3
Unique payers / 30d
Sep 6
Last called
exact
Payment scheme
Call this service
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";
const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const fetchWithPay = wrapFetchWithPayment(fetch, account);
const res = await fetchWithPay("https://402utils.com/v1/color", {
method: "GET",
});
const data = await res.json();curl -X GET \
"https://402utils.com/v1/color?bg=ffffff&fg=000000&op=contrast" \
-H "X-PAYMENT: <signed x402 payment>"Example response
{
"AA": {
"largeText": true,
"normalText": true,
"uiComponents": true
},
"AAA": {
"largeText": true,
"normalText": true
},
"bg": {
"hex": "#ffffff",
"input": "ffffff"
},
"fg": {
"hex": "#000000",
"input": "000000"
},
"op": "contrast",
"ratio": 21
}Payment details
0xc55a2d530b53cbad1001e4afd4720b7e71f9c291USD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913Is this your API?
Pin it to the top of Other and the homepage with a featured placement.
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Fetch an RSS 2.0 or Atom feed and return clean JSON: feed title, link and description, plus items with title, link, ISO-8601 publishedAt, summary and author. Handles both formats and normalises the dates. The caller-supplied URL is SSRF-checked; the fetch is capped at 2 MB and 8 s.
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Echoes back the JSON body you send, with a server timestamp. Useful for verifying your x402 client integration end to end.