Quickstart

1. Try it immediately (no account needed)

No signup, no API key. Anonymous callers get 5–10 free validation requests:

curl https://api.giltiq.de/v1/validate/DE811575812

You’ll get a full validation response immediately.

When the anonymous limit is reached, the API returns HTTP 401 with a machine-readable registration prompt:

{
  "error": "anonymous_limit_reached",
  "message": "Register for a free API key to continue (100 calls/month, no payment required).",
  "register_url": "https://giltiq.de/register"
}

2. Register for a free API key

Register for 100 free calls/month — no payment required, email is optional. At least one of email or agent_id must be provided.

With an email address:

curl -X POST https://api.giltiq.de/v1/register \
  -H "Content-Type: application/json" \
  -d '{"email": "you@example.com"}'

For agent or automated registration (no email needed):

curl -X POST https://api.giltiq.de/v1/register \
  -H "Content-Type: application/json" \
  -d '{"agent_id": "my-invoicing-agent"}'

The response contains your API key — save it now, it’s shown only once:

{
  "api_key": "gq_live_...",
  "message": "Save this key — it is only shown once."
}

3. Validate with your API key

Pass your key using the X-API-Key header:

curl https://api.giltiq.de/v1/validate/DE811575812 \
  -H "X-API-Key: gq_live_your_key_here"

Every response includes usage headers so you always know where you stand:

X-Giltiq-Usage: 1/100

That’s it. Check the API Reference for all available options, or the Authentication guide for the full tier model.