Error Rate Calculator
Calculate request error rate and success rate.
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Calculate request error rate
Error rate is a quick health signal for APIs, websites, background jobs and services. Enter failed requests and total requests to calculate error rate and success rate. It is useful for incident reviews, dashboards, QA checks, API monitoring and reliability notes.
Failed divided by total
Use the same time window and request source when comparing error rates.
Frequently asked questions
What is error rate?
It is failed requests divided by total requests.
Should 4xx responses count as errors?
It depends on your metric definition. Use the failed count that matches your dashboard.
Can this be used for jobs?
Yes. Treat failed jobs as failed requests and total jobs as total requests.