DAILY

Color of the Day API

GET/daily/color

Get a deterministic RGB hex color for the current UTC day.

No signup or API key required.

Parameters

No endpoint-specific parameters. Use format to choose the response representation.

formatenumoptional · query: Response format. Defaults to json.
jsontext

No request body. Unknown or repeated query parameters return HTTP 400.

Returns 200 OK

A JSON object with the following fields.

hexstring: Uppercase RGB hex color, including the leading #.
datestring: UTC selection date in YYYY-MM-DD format. Cached until midnight UTC; selections can repeat on later dates.

Plain text

With format=text: Only the hex value, without the JSON wrapper. The date is omitted.

Errors

Validation and service errors always return JSON, including when format=text.

errorstring: A machine-readable error code, such as invalid_parameter or rate_limited.
messagestring: A description of the problem.

400 Invalid parameters.

414 Query string exceeds 2048 characters.

429 Rate limit reached. Wait the seconds in Retry-After before retrying.

Usage notes

Deterministic hex color seeded by UTC date and endpoint name. Text returns the hex value. Cache expires at midnight UTC.

Coordinate a daily accent color across demo clients. The same date returns the same color, with a date field for identifying the selection.

Responses are cached until midnight UTC. Selections can repeat on later dates and can change when the content collection is updated. Browser requests are supported through open CORS.

120 requests per minute per IP, with up to 30 per 10 seconds, shared across APIs. Limits are approximate per Cloudflare location. Full usage limits ↗