PostalCodes vs PostcodeData.nl

Same instrument, two spec sheets — measured, not claimed.

Uptime · 30d
Uptime · 90d99.02%100%
Uptime · 30d98.3%100%
P50 · ms1030692
P95 · ms25941989
Authnonenone
CORSnoyes
HTTPSyesno
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree — limits not published
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

PostalCodes vs PostcodeData.nl: common questions

Which is more reliable, PostalCodes or PostcodeData.nl?

On our scheduled checks, PostcodeData.nl leads on measured uptime — PostalCodes at 99.02% versus PostcodeData.nl at 100% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Which is faster, PostalCodes or PostcodeData.nl?

PostcodeData.nl has the lower median latency in our checks — PostalCodes responds in 1030 ms versus PostcodeData.nl at 692 ms (P50). Tail latency (P95) is in the table above; for most workloads the median is the number that shapes how the API feels.

Do PostalCodes and PostcodeData.nl need an API key?

Neither needs a paid key — PostalCodes is callable with no signup, and PostcodeData.nl is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call PostalCodes and PostcodeData.nl from the browser?

Neither sends browser-friendly CORS headers reliably, so call PostalCodes and PostcodeData.nl from a server or proxy rather than client-side. The CORS and HTTPS rows above show exactly what we detected for each.

Are PostalCodes and PostcodeData.nl free for commercial use?

PostalCodes has unclear commercial terms, and PostcodeData.nl has unclear commercial terms. We track service terms and the data license as separate fields — see the Commercial use and Data license rows above, and confirm both before shipping either in a paid product.