Understanding Error Budget Remaining
How we calculate. Allowed downtime = period × (1 − SLO/100); remaining % = (allowed − downtime) ÷ allowed × 100. 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 Remaining case uses slo (%) 99.9 and period length 43200. Enter the same figures below to reproduce the worked path.
What is Error Budget Remaining?
The complement of error budget consumed. Teams often freeze risky releases when remaining budget nears zero.
- Same units for period and downtime
- SLO below 100% so allowed downtime is positive
- Pairs with consumed % on the Wave 1 tool
The Formula
Worked Example
Common Use Cases
- Release gates: freeze when remaining is low
- SLO reviews: leftover reliability allowance
- On-call dashboards: budget left this month
Pro Tips
- Align period with your SLO window (month/quarter)
- Include partial outages per severity policy
- Don’t double-count planned maintenance unless policy says so
Limitations: Error Budget Remaining results are educational DevOps/SRE/FinOps planning aids—not SLAs, billing guarantees, or operational policy. Confirm definitions with your platform and finance teams.
FAQ
How is this different from error budget consumed?
Consumed is downtime ÷ allowed × 100. Remaining is (allowed − downtime) ÷ allowed × 100 (floored at 0% if overspent).
What if SLO is 100%?
Allowed downtime is zero and remaining is undefined—use an SLO below 100%.
Authoritative References
For SRE and FinOps definitions, consult:
- Google SRE books — SLOs, error budgets, toil
- DORA — delivery performance research
- FinOps Foundation — cloud cost practices