How is Uptime Percentage Calculated?
Uptime percentage tells you what proportion of checks returned a successful (online) status.
The formula
Uptime % = (Successful Checks / Total Checks) × 100
A "successful check" is any check where your store's status was Up. Checks with Down or Degraded status are not counted as successful.
What the numbers mean
- 100% — Every single check was successful. Your store had no detected downtime.
- 99.9% — Out of 1,000 checks, 1 was not successful. Very good.
- 99% — Out of 1,000 checks, 10 were not successful. Generally acceptable.
- Below 99% — Indicates notable downtime that may be worth investigating.
Time periods
Blimey shows uptime percentages for four periods:
- 24 Hours — Very recent performance
- 7 Days — Weekly reliability
- 30 Days — Monthly reliability
- 90 Days — Quarterly reliability
Important notes
- Uptime is calculated from actual check data, not estimated
- If you change your check interval, the total number of checks changes, but the percentage remains meaningful
- Brief outages that resolve quickly still count as failed checks in the percentage calculation