Codeforces

Overview

The Codeforces API exposes competitive programming data — problems, contests, submissions, and user ratings. Public endpoints are keyless (verified live); API keys only enable the write/private endpoints.

Quick Start

Problem set (verified live):

curl "https://codeforces.com/api/problemset.problems"

{
  "status": "OK",
  "result": {
    "problems": [
      { "contestId": 4, "index": "A", "name": "Watermelon", "tags": ["brute force", "math"] }
    ],
    "problemStatistics": []
  }
}

User info:

curl "https://codeforces.com/api/user.info?handles=tourist"

Contest list:

curl "https://codeforces.com/api/contest.list"

Authentication

• Public endpoints: none (keyless).
• Private endpoints (user submissions by handle, etc.): API key + secret with apiSig signing — see apiHelp.

Rate Limits & Notes

• Public API: ~1 request/2 seconds per IP — be polite.
• Every response has a status field: "OK" or "FAILED" (with comment).
• Data covers all Codeforces rounds, problems with tags/difficulty, and user ratings.
• The problem set is large (2.2MB+ of JSON) — cache it.

FAQ

Is Codeforces API free? Yes — public data is keyless (verified).

Do I need a key? Only for private/user-scoped endpoints — reads work anonymously.

What’s the rate limit? ~1 request/2 seconds per IP.