US ZipCode vs ViaCep
Same instrument, two spec sheets — measured, not claimed.
US ZipCode vs ViaCep: common questions
Which is more reliable, US ZipCode or ViaCep?
On our scheduled checks, ViaCep leads on measured uptime — US ZipCode at —% versus ViaCep at —% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.
Do US ZipCode and ViaCep need an API key?
ViaCep needs no key, while US ZipCode requires a free API key. If you want to start calling without signup, reach for ViaCep first.
Can I call US ZipCode and ViaCep from the browser?
Yes — both US ZipCode and ViaCep send CORS headers over HTTPS, so front-end code can fetch either directly with no backend proxy. That makes them easy to swap in a client-side app while you compare responses.
Are US ZipCode and ViaCep free for commercial use?
US ZipCode has unclear commercial terms, and ViaCep 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.