Uptime SLA Calculator
Turn nines into real downtime budgets.
Per day
1.4 min
Per week
10.1 min
Per month (30d)
43.2 min
Per quarter
2.2 h
Per year
8.8 h
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About this tool
An SLA percentage is abstract until you convert it into minutes. Three nines allows about 43 minutes of downtime a month; four nines allows just over four. That gap is the difference between manual and automated recovery.
Error budgets
The downtime you are allowed is a budget. Spend it deliberately on deploys and maintenance rather than discovering it during an incident.
Composite availability
Chained dependencies multiply. Five services at 99.9% each give roughly 99.5% end to end.
How to use Uptime SLA Calculator
- 1
Open Uptime SLA Calculator
Everything runs on this page — there is nothing to install and no account required to use the free features.
- 2
Add your input
Paste or enter your values in the panel above. The tool updates as you type, so you can iterate quickly.
- 3
Review the output
Check the result, copy it with one click, and adjust the options until it matches what your system expects.
- 4
Take it further
Use the security & infrastructure tips below to make the result production-ready, then unlock the gated extras via the form above.
Best practices
- Treat every result as a snapshot — configuration drifts, so re-check after each deploy.
- Fix the highest-impact finding first rather than chasing a perfect score.
- Apply changes at the shared layer (proxy, CDN, base image) so every service inherits them.
- Document what you changed and when; auditors and future teammates will ask.
Why Uptime SLA Calculator matters
Infrastructure and security misconfigurations are among the most common root causes of real incidents, and almost all of them are cheap to fix once visible.
Leaving them unaddressed means failed audits, blocked enterprise deals, and avoidable exposure.
Related free & paid tools
| Tool name | Type | Key features | Link |
|---|---|---|---|
| UptimeRobotOffer | Freemium | Monitoring with public status pages and SLA reports | Visit |
| Better StackOffer | Freemium | Uptime monitoring, on-call and incident timelines | Visit |
| StatuspageOffer | Paid | Customer-facing status and uptime communication | Visit |
| Google SRE Workbook | Free | How to set error budgets behind an SLA | Visit |
Links marked Offer may be partner links. They cost you nothing extra and never affect which tools we recommend.