free_tool
SLO & Error Budget Calculator
"Five nines" sounds reassuring until you see it in minutes. Pick an availability target and get the downtime it actually permits, a request error budget, and the burn rate that says when to stop shipping features and go fix reliability.
Allowed downtime at 99.9%
43m 12s/ 30d
1m 26s / day · 8h 46m / year
2.5K of 5K failures still in budget.
Want these numbers to mean something in production? I'll help you set SLOs that map to real user pain — and wire the alerts to enforce them.
Set up SLOs that hold — book a callBudgets shown over a 30-day window. Pure arithmetic from the target — no hidden assumptions. Share the link to compare targets with your team.
how_it_works
From a target to an enforceable budget
Your error budget is simply the gap between your target and 100%. A 99.9% target means 0.1% of requests — or about 43 minutes a month — are allowed to fail. That budget is something to spend deliberately on risky deploys, not a number to fear.
The burn rate tells you how fast you're using it. Burning at 1× means you'll spend exactly the month's budget over the month; at 14.4× you'll blow a 30-day budget in roughly two days — the classic threshold for a fast-burn page. When the budget's gone, the policy writes itself: stop shipping, fix reliability.