Test thoroughly before production so checkout never breaks for real customers.
A safe testing checklist
- Use a dedicated test API key, separate from production
- Verify valid postcodes return the expected addresses
- Send malformed input to confirm your error handling
- Check rate-limit behaviour and your retry/backoff logic
- Confirm the manual-entry fallback works when the API is unavailable
Going live
Switch to your production key from authentication & keys, then watch request logs for the first live traffic.
Related
Review error handling and the API changelog for recent changes.
Frequently asked questions
How do I test the API without affecting production?
Use a separate test API key and sample postcodes to verify your integration, then switch to your production key when ready.
Are there sample postcodes I can use?
Yes — use well-known valid postcodes to confirm responses, and malformed inputs to check your error handling.
How do I go live?
Swap your test key for a production key, confirm rate limits suit your volume, and monitor your request logs.
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