Nager.Date vs Slack
Same instrument, two spec sheets — measured, not claimed.
Nager.Date vs Slack: common questions
Which is more reliable, Nager.Date or Slack?
On our scheduled checks, Slack leads on measured uptime — Nager.Date at —% versus Slack 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 Nager.Date and Slack need an API key?
Nager.Date needs no key, while Slack requires a free API key. If you want to start calling without signup, reach for Nager.Date first.
Can I call Nager.Date and Slack from the browser?
Yes — both Nager.Date and Slack 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 Nager.Date and Slack free for commercial use?
Nager.Date has unclear commercial terms, and Slack 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.