SLA Uptime Calculator
Translate availability percentages into exact daily, weekly, monthly, and yearly allowed downtime budgets.
Slide the bar or enter a custom percentage below.
Allowed in 24 hours
Allowed in 7 days
Allowed in 30.4 days
Allowed in 91.3 days
Allowed in 365 days
Recommended Monitoring: 1-minute checks
Allowed monthly downtime is 43.8 minutes. This is the sweet spot for modern SaaS. Requires automated alerts to Slack, WhatsApp, or Discord so support and engineering teams can respond within 15 minutes of an outage.
Pingzo provides flat-rate 1-minute monitoring checks, public status pages, and instant alerts via WhatsApp, Telegram, Discord, and email to ensure you never breach your SLA target.
Start Free MonitoringUnderstanding SLAs, SLOs, and SLIs
Managing infrastructure availability requires clear distinctions between measurement, internal objectives, and legal commitments:
- 1. SLI (Service Level Indicator)The real-time metric measured to gauge compliance, such as the success rate of HTTP requests (e.g. 99.98% of pings returned HTTP 200).
- 2. SLO (Service Level Objective)The target goal set by engineers to maintain safety margins (e.g. "We aim for 99.9% availability every quarter").
- 3. SLA (Service Level Agreement)The legally binding agreement with users promising compensation if availability falls below a specific threshold.
The Availability "Nines" Table
Use this standard reference chart to see how allowed downtime budgets compress as nines are added:
| Availability | Daily | Monthly | Yearly |
|---|---|---|---|
| Two Nines (99%) | 14m 24s | 7h 18m 17s | 3d 15h 36m |
| Three Nines (99.9%) | 1m 26s | 43m 48s | 8h 45m 36s |
| Three Nines Five (99.95%) | 43s | 21m 54s | 4h 22m 48s |
| Four Nines (99.99%) | 8.6s | 4m 22s | 52m 34s |
| Five Nines (99.999%) | 0.86s | 26s | 5m 15s |
Frequently Asked Questions
Common questions developers have about SLA calculation and uptime thresholds.
What is a Service Level Agreement (SLA)?
An SLA is a formal, legal contract between a service provider and its customers defining the expected level of service, specifically minimum uptime percentages. Failing to meet these targets usually results in financial penalties or service credits.
What is the difference between SLA, SLO, and SLI?
SLIs (indicators) are the raw metrics you measure (e.g. error rate, response times). SLOs (objectives) are internal goals your engineering team targets (e.g., maintaining 99.95% uptime). SLAs (agreements) are the official commitments made to customers based on those SLOs.
Does SLA allowed downtime include planned maintenance?
Usually, yes, unless explicitly excluded in the customer agreement. In many SLAs, planned maintenance windows (configured during off-peak hours) are exempted from the uptime calculation if customers are notified in advance.
How does check frequency affect SLA compliance?
If you have a 99.99% SLA, your monthly allowed downtime is only 4 minutes and 22 seconds. If your monitoring tool checks your service only once every 5 minutes, a single failed check that resolves immediately can instantly breach your monthly downtime budget. You must use 1-minute checking intervals to alert your team immediately.
Protect Your SLA Target with Pingzo
Get 1-minute synthetic checks and instant alerts delivered to your team on WhatsApp, Discord, and Telegram before downtime breaches your SLA.