OkSurf vs Open Library
Same instrument, two spec sheets — measured, not claimed.
OkSurf vs Open Library: common questions
Which is more reliable, OkSurf or Open Library?
On our scheduled checks, OkSurf leads on measured uptime — OkSurf at 100% versus Open Library 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, OkSurf or Open Library?
OkSurf has the lower median latency in our checks — OkSurf responds in 624 ms versus Open Library at 1629 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 OkSurf and Open Library need an API key?
Neither needs a paid key — OkSurf is callable with no signup, and Open Library is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call OkSurf and Open Library from the browser?
Only Open Library is browser-friendly — it returns CORS headers over HTTPS. OkSurf needs a server-side call or proxy, so factor that into which one fits a front-end project.
Are OkSurf and Open Library free for commercial use?
OkSurf has unclear commercial terms, and Open Library 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.