Appointment Scheduling Software · reliability comparison
Cal.com vs OnceHub: which is more reliable? (2026)
Cal.com is more reliable than OnceHub, scoring 86.2 vs 74.8 out of 100. Over the last 90 days Cal.com reported 3 incidents and OnceHub reported 2, with effective uptime of 100% and 99.67% respectively.
Data updated Nov 1, 2026 · How we score
| Metric | Cal.com | OnceHub |
|---|---|---|
| Reliability score | 86.2 | 74.8 |
| Rank (scheduling apps) | #6 | #7 |
| Uptime (90 days) | 100% | 99.67% |
| Incidents (90 days) | 3 | 2 |
| Partial / major outages | 2 | 2 |
| Avg time to resolve | — | 7h 8m |
| Outages we detected | 0 | 0 |
| Transparency score | 100/100 | 100/100 |
Where Cal.com and OnceHub differ
- Cal.com reported 50% more incidents than OnceHub over the last 90 days (3 vs 2).
90-day uptime
Cal.com
OnceHub
- No incidents
- Degraded
- Partial outage
- Major outage
- No data
Recent Cal.com incidents
- Partial outageOct 24, 2026 · resolved (duration not published)
Resolved - Identified - Issues with Enterprise SAML Authentication
- Degraded performanceSep 15, 2026 · resolved (duration not published)
- Major outageAug 31, 2026 · resolved (duration not published)
Resolved - Major outage: We resolved an issue impacting the API - https://api.cal.com/
Recent OnceHub incidents
- Partial outageSep 8, 2026 · resolved in 13h 25m
Ongoing maintenance with one of our service providers is causing delays in the delivery of SMS two-factor authentication (2FA) codes, which official update ↗
Affected: User Application
- Partial outageAug 26, 2026 · resolved in 50m
We have identified an issue related to signing in using Microsoft or Google.
Affected: User Application
Other scheduling apps to consider
- Calendly · #1 · 100% uptime
- Doodle · #2 · 100% uptime
- SavvyCal · #3 · 100% uptime
- Sign In Scheduling (formerly 10to8) · #4 · 100% uptime
See the full most reliable appointment scheduling software ranking →