Error Budget Burn Rate

A classic SRE multi-window alerting signal. Burn rate 1 means you are on track to exhaust the budget exactly at period end; above 1 means overspending.

Burn rate = (error budget consumed %) ÷ (percent of SLO period elapsed).

Tip: Keep “Error Budget Consumed (%)” and “Period Elapsed (%)” on the same basis (period, units, and population) before calculating Error Budget Burn Rate.

Cluster: DevOps hub · Deployment frequency · Software Testing hub · Percentage guide

Burn rate compares how fast you are spending the error budget to how far you are through the SLO window.

Enter error budget consumed % and percent of the period that has elapsed.

Share of allowed downtime already used
Percent of the SLO window that has passed

Burn Rate

Understanding Error Budget Burn Rate

How we calculate. Burn rate = (error budget consumed %) ÷ (percent of SLO period elapsed). The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.

Real-world scenario: A typical Error Budget Burn Rate case uses error budget consumed (%) 40 and period elapsed (%) 20. Enter the same figures below to reproduce the worked path.

What is Error Budget Burn Rate?

A classic SRE multi-window alerting signal. Burn rate 1 means you are on track to exhaust the budget exactly at period end; above 1 means overspending.

  • Consumed % from your SLO math
  • Elapsed % = time passed ÷ period × 100
  • Alert on sustained high burn

The Formula

Error Budget Burn Rate
Burn rate = Consumed % ÷ Period elapsed %

Worked Example

Scenario: Consumed 40% of budget; 20% of the month has elapsed.
Step 1: Burn rate = 40 ÷ 20 = 2
Answer: Burn rate is 2× (spending twice as fast as a linear budget).

Common Use Cases

  • Page policies: multi-window burn alerts
  • Incident response: stop the bleed
  • SLO coaching: early-month risk

Pro Tips

  • Use short and long windows together
  • Recalculate after major incidents
  • Pair with remaining %

Limitations: Error Budget Burn Rate results are educational DevOps/SRE/FinOps planning aids—not SLAs, billing guarantees, or operational policy. Confirm definitions with your platform and finance teams.

FAQ

What does burn rate 1 mean?

You are consuming budget at a pace that would hit 100% consumed exactly at period end—if the rate continues.

What if period elapsed is 0?

Burn rate is undefined—wait until some of the window has elapsed.

Authoritative References

For SRE and FinOps definitions, consult: