IsItWater vs US ZipCode
Same instrument, two spec sheets — measured, not claimed.
IsItWater vs US ZipCode: common questions
Which is more reliable, IsItWater or US ZipCode?
On our scheduled checks, US ZipCode leads on measured uptime — IsItWater at —% versus US ZipCode 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 IsItWater and US ZipCode need an API key?
Both ask you to authenticate — IsItWater uses an API key and US ZipCode uses an API key. Each key is free to obtain; the Auth and Card-required rows above spell out the signup terms.
Can I call IsItWater and US ZipCode from the browser?
Only US ZipCode is browser-friendly — it returns CORS headers over HTTPS. IsItWater needs a server-side call or proxy, so factor that into which one fits a front-end project.
Are IsItWater and US ZipCode free for commercial use?
IsItWater has unclear commercial terms, and US ZipCode 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.