ipapi.co vs SLF
Same instrument, two spec sheets — measured, not claimed.
ipapi.co vs SLF: common questions
Which is more reliable, ipapi.co or SLF?
On our scheduled checks, SLF leads on measured uptime — ipapi.co at 1.0% versus SLF 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, ipapi.co or SLF?
SLF has the lower median latency in our checks — ipapi.co responds in 440 ms versus SLF at 213 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 ipapi.co and SLF need an API key?
Neither needs a paid key — ipapi.co is callable with no signup, and SLF is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call ipapi.co and SLF from the browser?
Yes — both ipapi.co and SLF 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 ipapi.co and SLF free for commercial use?
ipapi.co has unclear commercial terms, and SLF 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.