ELI vs Userstack
Same instrument, two spec sheets — measured, not claimed.
ELI vs Userstack: common questions
Which is more reliable, ELI or Userstack?
Both are neck-and-neck — ELI and Userstack each measure 99.02% uptime over 90 days on our probe schedule. Reliability here is verified from our own scheduled checks; use the 30-day bars above to see which has been steadier lately.
Which is faster, ELI or Userstack?
Userstack has the lower median latency in our checks — ELI responds in 591 ms versus Userstack at 443 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 ELI and Userstack need an API key?
Both ask you to authenticate — ELI uses an API key and Userstack 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 ELI and Userstack from the browser?
Yes — both ELI and Userstack 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 ELI and Userstack free for commercial use?
ELI has unclear commercial terms, and Userstack 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.