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Uptime / SLA calculator

Turn an uptime percentage into allowed downtime per year, month and day.

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Need Downtime/year (min), Downtime/month (min), Downtime/day (sec)? The Uptime / SLA calculator derives it from Uptime (%) in one step. For instance, with Uptime (%) = 99.9 it returns Downtime/year (min) = 525.6, Downtime/month (min) = 43.8 and Downtime/day (sec) = 86.4.

How to use it

  1. Enter your values: Uptime (%).
  2. Read the result instantly: Downtime/year (min), Downtime/month (min), Downtime/day (sec).

Frequently asked questions

What does the Uptime / SLA calculator actually compute?

It takes Uptime (%) and derives Downtime/year (min), Downtime/month (min) and Downtime/day (sec) from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

A single value: Uptime (%). Nothing else is required — no account, no file upload.

Can you show a worked example?

With Uptime (%) = 99.9, the calculator returns Downtime/year (min) = 525.6, Downtime/month (min) = 43.8 and Downtime/day (sec) = 86.4. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

What happens if I enter larger values?

It moves a lot. Using Uptime (%) = 199.8 instead, Downtime/year (min) goes from 525.6 to -524,549 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Uptime (%) = 49.95, Downtime/year (min) comes out at 263,063. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Finding out how big a thing will be before you make it: how many gigabytes an hour of footage takes, how long a file needs on the connection you have, how large a photo prints before it goes soft, what bitrate fits the budget you were given.

What is the most common mistake?

Reading a figure in one unit next to a figure in another. Megabits are not megabytes and the eight-fold gap sinks most transfer estimates; a kilobyte is 1 000 bytes to a drive maker and 1 024 to the operating system; pixels are not dots per inch. None of it is hard arithmetic — the unit on each side is what decides whether the answer means anything.

What is the difference between the Uptime / SLA calculator and the Data usage calculator?

This one returns Downtime/year (min) and Downtime/month (min); the Data usage calculator returns Total data (GB). That is the whole difference — open the one whose figure you need.

Where do the figures come from, and how current are they?

Byte prefixes follow the IEC convention where a kibibyte is 1 024 bytes and a kilobyte is 1 000 — drive makers use the second, operating systems often report the first, and a disk that shrinks on arrival is that gap and nothing else. Print sizing assumes 300 dpi unless you change it.

Further reading

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