Free Uptime Monitoring Tools

Calculators, benchmarks, and reference data for developers building reliable services. No account required.

Uptime Calculator

Convert uptime percentages to allowed downtime per year, month, week, and day. Use this to set SLA targets or evaluate what a given percentage actually means.

Per year

8h 45m

Per month

43m 49s

Per week

10m 4s

Per day

1m 26s

Response Time Benchmarks

What counts as fast, acceptable, and slow for web applications. Reference these when setting alert thresholds for your monitors.

Under 200ms Excellent
200–500ms Good
500ms–1s Acceptable
1–3s Slow — alert threshold
Over 3s Critical

Source: Google research shows that 53% of mobile users abandon a page that takes more than 3 seconds to load. 1s is a common SLA target for API endpoints. Configure slow-response alerts in PingBase for your monitors.

SLA Reference Table

How much downtime each uptime SLA level actually allows. Use this when writing SLA commitments in contracts or evaluating vendor SLAs.

Uptime Per year Per month
99.999%5m 15s26s
99.99%52m 35s4m 22s
99.9%8h 45m43m 49s
99.5%1d 19h3h 38m
99%3d 15h7h 17m
95%18d 6h1d 13h

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PingBase gives you uptime monitoring, status pages, and SSL monitoring on the free tier. No credit card required.

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