Downtime Calculator

Calculate and compare service downtime based on uptime percentages

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Common uptime SLAs:

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Common Uptime Examples

99.9% Uptime

≈ 43.8 minutes/month

This level of availability is common for commercial hosting services.

99.99% Uptime

≈ 4.38 minutes/month

Often referred to as 'four nines,' this is expected for high-availability systems.

99.999% Uptime

≈ 26.3 seconds/month

Also known as 'five nines,' typical for mission-critical systems like financial or healthcare services.

Frequently Asked Questions

What is uptime?

Uptime refers to the time a service is available and operational. It's typically measured as a percentage of total time.

What is downtime?

Downtime is the period when a service is unavailable or not functioning as intended. This could be due to maintenance, failures, or other issues.

What is considered good uptime?

For most business services, 99.9% uptime is considered good. Mission-critical systems often aim for 99.999% ("five nines") or better.

Why is uptime important?

Uptime is crucial for business continuity, user satisfaction, and maintaining service level agreements (SLAs). Even small amounts of downtime can have significant impacts on operations and revenue.

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Calculations are approximate and may vary based on actual calendar months and leap years.