Documentation • REST API

OpenFileConverter API Reference

Guides

Base URL

https://openfileconverter.com/api/convert/

The convert endpoint accepts a multipart POST with a file field and a target_format field, and returns the conversion result with a one-hour download URL. Uploads are capped at 50 MB.

Authentication

No account or API key is needed. Send a client-issued opaque session token (8–64 characters: A-Z a-z 0-9 - _) as a bearer credential. Quota is tracked per token and per network.

Authorization: Bearer <your-session-token>

Issued team API keys are on the roadmap; the session-token contract above is the supported authentication today.

Limits & Quota

Free usage allows 5 per day conversions on standard pairs (2 per day for medium-cost pairs), counted per session and per client network. Pro raises the ceiling to 500 per day for $12/month via Stripe checkout.

Unsupported pairs return HTTP 422 with an explicit in-rollout notice — the API never reports a fabricated completed status.

MCP for AI Agents

A Model Context Protocol server exposes the same capabilities over JSON-RPC 2.0 at /api/v1/mcp/, with discovery at /.well-known/mcp.json.

cURL

curl -X POST https://openfileconverter.com/api/convert/ \
  -H "Authorization: Bearer $SESSION_TOKEN" \
  -F "target_format=webp" \
  -F "file=@photo.png"

← HTTP 200

{"status": "completed", "target_size_bytes": 184320, "duration_ms": 612, "download_url": "/download/<job-uuid>/?fmt=webp", "download_expires_in": 3600}

Unsupported pairs: HTTP 422 {"status": "in_rollout", ...}