Paste a URL below. Get an instant health check — then we'll watch it every minute and alert you the second it fails.
Check your endpoint
No account needed to check. Results in under 10 seconds.
Recovered · api.yourapp.com
Down 1m 42s · Alert sent to Slack
Response
142ms
SSL
Valid
Incidents
1 / 50d
SSL expires in 14 days
cert.yourapp.com
How it works
No dashboards to build. No alert policies to write. Paste a URL and Whistlrr handles everything else.
HTTP, HTTPS, or TCP — paste it in. Checks start within seconds. No agents, no code, no YAML, no deploy.
Email is included free. Slack, PagerDuty, and Teams on paid plans. One destination is usually enough.
Down alert when it fails. Recovery alert when it's back. Full incident timeline is in your dashboard.
Features
Free plan checks every 5 minutes. Pro and Business every 1 minute. Shorter intervals = faster alerts when something breaks.
Checks run from US East and EU West simultaneously. A failure across all regions is a real outage — not a datacenter blip.
We alert you before your certificate expires — because a lapsed cert looks exactly like downtime to every single user.
Route alerts to where your team actually responds. Each monitor can route to a different channel.
A hosted page showing your service uptime history. Link to it from your docs or your support flow.
Your cron job pings our endpoint on every run. If we stop hearing from it within the expected window, we alert you.
Pricing
Free plan is genuinely free — not a 14-day trial. Upgrade when you need more.
Pro
Business
Annual billing saves 20%. Full feature comparison →
Find out what they see before they have to tell you. Paste your URL above — it takes 10 seconds.