Universalis vs Zelda
Same instrument, two spec sheets — measured, not claimed.
Universalis vs Zelda: common questions
Which is more reliable, Universalis or Zelda?
On our scheduled checks, Zelda leads on measured uptime — Universalis at —% versus Zelda at —% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.
Do Universalis and Zelda need an API key?
Neither needs a paid key — Universalis is callable with no signup, and Zelda is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call Universalis and Zelda from the browser?
Yes — both Universalis and Zelda 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 Universalis and Zelda free for commercial use?
Universalis has unclear commercial terms, and Zelda 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.