Error Budget Calculator
Calculate failed-request allowance for a request success objective.
Your inputs
Calculation results
Formula & assumptions
Budget = requests × (1−success target); whole-request allowance rounds down.
Values use the specified units. Calculations use floating-point arithmetic. Check input measurements and formula assumptions before applying the result.
Compare your scenarios
Save up to five results to compare changes side by side. Scenarios stay in this tab until you clear or reload it.
Using Error Budget Calculator
Calculate failed-request allowance for a request success objective.
- Enter requests, success target, observed failures using the units printed under each field.
- Choose Calculate, or enable live updates. Review the result labels and formula assumptions.
- Save scenarios to compare up to five variations, then copy the report or download JSON or CSV.
Example
Requests: 1000000 requests Success target: 99.95 percent Observed failures: 120 requests Allowed failed requests: 500 Remaining failed-request budget: 380 Observed success · percent: 99.988
Questions & answers
What does Error Budget Calculator calculate?
Calculate failed-request allowance for a request success objective.
Which units should I enter?
Requests uses requests. Success target uses percent. Observed failures uses requests. Convert values to these units before calculating.
Which formula does it use?
Budget = requests × (1−success target); whole-request allowance rounds down.
What does the included example show?
Requests: 1000000 requests; Success target: 99.95 percent; Observed failures: 120 requests. Result: Allowed failed requests = 500; Remaining failed-request budget = 380; Observed success · percent = 99.988.
Can I compare different settings?
Yes. Save a scenario, change the inputs and save another result. Up to five scenarios are compared in this tab; they disappear when you reload or leave.
Can I export the calculation?
Copy the JSON report or download JSON and CSV with inputs, result labels and numeric values. Processing uses local JavaScript; no calculation request is sent to our server. Displayed values use up to 10 significant digits; exports retain JavaScript numeric precision.
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