---
title: "Check WCAG contrast between a foreground and background color."
method: POST
path: "/api/v1/contrast"
tags: ["Converters"]
---

# Check WCAG contrast between a foreground and background color.

`POST /api/v1/contrast`

## Request

- Base URL: `https://programmes.net`
- URL: `https://programmes.net/api/v1/contrast`
- Auth: none declared

Color Contrast Checker. Operations: `check` — Compute the contrast ratio and WCAG pass/fail for a color pair. `best-text` — Pick black or white text for the best contrast on a background.

## Request body

- union
  - ContrastCheck: Compute the contrast ratio and WCAG pass/fail for a color pair.
    - `operation` 'check', required
    - `input` string: The foreground color (#rrggbb, #rgb or rgb(...)).
    - `options` object, required
      - `background` string, required: The background color.
  - ContrastBestText: Pick black or white text for the best contrast on a background.
    - `operation` 'best-text', required
    - `input` string: The background color.
    - `options` object

## Response `200`

The operation ran.

- object
  - `ok` unknown, required
  - `tool` 'contrast', required
  - `operation` 'check' | 'best-text', required
  - `result` unknown, required

## Other responses

- `400`: The request is not valid (https://programmes.net/api#invalid-request); The tool has no such operation (https://programmes.net/api#unknown-operation)
- `404`: No such tool (https://programmes.net/api#unknown-tool)
- `413`: The request or its input is too large (https://programmes.net/api#content-too-large)
- `415`: The body must be JSON (https://programmes.net/api#unsupported-media-type)
- `422`: An option is missing, of the wrong type or out of range (https://programmes.net/api#invalid-options); This call needs more CPU than one API call may use (https://programmes.net/api#refused); The operation could not process the input (https://programmes.net/api#tool-error)
- `429`: Too many requests (https://programmes.net/api#rate-limited)
- `500`: Internal error (https://programmes.net/api#internal-error)

---

[API](https://skmtc.dev/programmes/apis/programmes-net-api.md) · [All operations](https://skmtc.dev/programmes/apis/programmes-net-api/llms.txt) · [OpenAPI document](https://skmtc.dev/programmes/apis/programmes-net-api/revisions/aa939784a2e6?raw)