FilterLists vs Portscan
Same instrument, two spec sheets — measured, not claimed.
FilterLists vs Portscan: common questions
Which is more reliable, FilterLists or Portscan?
On our scheduled checks, Portscan leads on measured uptime — FilterLists at 98.0% versus Portscan at 99.02% 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, FilterLists or Portscan?
Portscan has the lower median latency in our checks — FilterLists responds in 357 ms versus Portscan at 335 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 FilterLists and Portscan need an API key?
Neither needs a paid key — FilterLists is callable with no signup, and Portscan is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call FilterLists and Portscan from the browser?
Only Portscan is browser-friendly — it returns CORS headers over HTTPS. FilterLists needs a server-side call or proxy, so factor that into which one fits a front-end project.
Are FilterLists and Portscan free for commercial use?
FilterLists has unclear commercial terms, and Portscan 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.