The short version
UptimeRobot's free tier gives you 50 monitors with 5-minute intervals. Sentro gives you 5 monitors on free, but the paid plans are where Sentro wins: $4/mo vs $7/mo for comparable features, with Slack, Discord, Teams, Telegram, PagerDuty, and OpsGenie all included at lower price points.
Monitor types
Both tools support HTTP, TCP, ping, keyword monitoring, and SSL certificate monitoring. Sentro adds DNS record monitoring, domain expiry monitoring, heartbeat/cron monitoring, and a three-state model (UP / DEGRADED / DOWN) that UptimeRobot doesn't have. UptimeRobot's cron monitoring is limited to higher tiers; Sentro includes heartbeats on all plans (1 on Free, 5 on Starter).
Notification channels
UptimeRobot's free plan sends email alerts. Slack, Teams, and Discord require a paid plan — and Teams/Discord require the $20/mo plan or higher. Sentro includes Slack and Discord on Starter ($4/mo), Teams, Telegram, Google Chat, and Mattermost on Pro ($9/mo), and PagerDuty and OpsGenie on Max ($19/mo). PagerDuty is not available on UptimeRobot at any price.
Status pages
Both offer public status pages. Sentro's status pages come with subscriber email notifications on Starter+, custom domains on Max, white-label branding removal on Max, and a design that doesn't look like it was built in 2012. UptimeRobot's status pages are functional but visually dated, and custom domains require a $20/mo plan.
Pricing comparison
| Feature | Sentro | UptimeRobot |
|---|---|---|
| Free monitors | 5 | 50 |
| Paid entry price | $4/mo | $7/mo |
| Slack on lowest paid plan | Yes ($4/mo) | Yes ($7/mo) |
| Discord | $4/mo | $20/mo |
| Microsoft Teams | $9/mo | $20/mo |
| Telegram | $9/mo | Not available |
| PagerDuty | $19/mo | Not available |
| Custom domain status pages | $19/mo | $20/mo |
| Escalation policies | $9/mo | Not available |
| Self-hosted option | From $0 | Not available |
The verdict
If you need 50 free monitors and email-only alerts, UptimeRobot's free plan is unbeatable. If you want modern alerting channels, escalation policies, or are going to pay for a plan anyway — Sentro wins on almost every dimension and costs less at comparable tiers.
Get started
Start monitoring for free
5 monitors, 5-minute intervals, email + Slack alerts. No credit card required.