How to read a 95th percentile bandwidth bill
What you are really billed for, and why your peak isn't the number that counts.
By the Autoprator team. Updated .
Many upstream providers bill on the 95th percentile, not your highest peak. It helps to know how the number is made.
How it works
The provider samples your traffic, often every five minutes. At month end the samples are sorted, the top 5% are dropped, and you pay for the highest one left. In a 30-day month that ignores your busiest 36 hours.
What to check
Compare what you commit to with your real 95th percentile. A big gap means you may be paying for capacity you never use.
Be careful with backups
A quiet link isn't always a wasted one. It may have to carry everything when the other one fails, so size it for that day.