API Reference

Umsatzsteuer-Umrechnungskurse

A token-authenticated JSON API over the monthly euro reference rates published by the Bundesfinanzministerium for VAT declarations under § 16 Abs. 6 UStG.

Authentication

Send your API key in the Authorization header on every request to /api/v1/*.

curl -H "Authorization: Bearer ukk_…" \
  https://ukk-api.xevieso.com/api/v1/currencies

Rate limiting

60 requests per minute per key (sliding window). Responses include X-RateLimit-Limit, X-RateLimit-Remaining, and X-RateLimit-Reset. Exceeding the limit returns 429 with a Retry-After header.

Endpoints

GET/api/v1/currencies

GET/api/v1/rates/monthly?currency=USD&year=2025&month=3

GET/api/v1/rates/monthly?currency=USD&year=2025

GET/api/v1/rates/yearly?currency=USD&year=2024

GET/api/v1/rates?currency=USD&from=2024-01&to=2025-12

GET/api/v1/convert?amount=100&from=USD&to=EUR&year=2025&month=3

Data source

Rates are ingested monthly from the PDFs published by the Bundesfinanzministerium. Yearly averages are recomputed once the ministry's Gesamtübersicht confirms all twelve months.