Open Notify vs TLE
Same instrument, two spec sheets — measured, not claimed.
Open Notify vs TLE: common questions
Which is more reliable, Open Notify or TLE?
On our scheduled checks, TLE leads on measured uptime — Open Notify at 71.6% versus TLE at 88.2% 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, Open Notify or TLE?
Open Notify has the lower median latency in our checks — Open Notify responds in 241 ms versus TLE at 1090 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 Open Notify and TLE need an API key?
Neither needs a paid key — Open Notify is callable with no signup, and TLE is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call Open Notify and TLE from the browser?
Only TLE is browser-friendly — it returns CORS headers over HTTPS. Open Notify needs a server-side call or proxy, so factor that into which one fits a front-end project.
Are Open Notify and TLE free for commercial use?
Open Notify has unclear commercial terms, and TLE 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.