# Uptime

> The share of time a service is available. 99.9% allows about 43 minutes of downtime in 30 days; 99.99% about 4.3 minutes.

URL: https://pagerless.dev/glossary/uptime
Updated: 2026-10-22

## In Pagerless

Work it out with the [uptime calculator](https://pagerless.dev/tools/uptime-calculator).

## Related terms

- [SLA](https://pagerless.dev/glossary/sla): Service level agreement: a contract with users that includes consequences for meeting or missing the SLOs it contains.
- [SLO](https://pagerless.dev/glossary/slo): Service level objective: a target value or range for an SLI, such as 99.9% of requests succeeding over 30 days.