Uptime & SLA calculator

Calculate the allowed downtime per day, week, month and year for an availability percentage such as 99.9% or 99.99%.

Runs in your browser · nothing is sentCapacity & reliability

Availability (%)

Allowed downtime

99.9%

Enter an availability percentage and see how much downtime it allows. Use the presets for common targets.

🔒 Your input stays in your browser and is never sent anywhere.

How much downtime is 99.9%?

About 8 hours 46 minutes per year, or roughly 43 minutes per month.

Duration converterConvert seconds to days, hours and minutes and back. Accepts input such as 1d 2h 30m.
Cron expression explainerTurn a cron expression into readable text. With examples such as every 5 minutes or every Monday at 9:00.

Found a problem or have a suggestion? Tell us