API Response Time SLA Calculator
Paste response times and test them against a latency objective.
What this calculator measures
A response-time objective says what share of requests must finish at or below a threshold. “99% under 200 ms” means no more than 1% of the measured requests may exceed 200 ms. Availability and latency are separate: an API can return successful responses and still miss its performance objective.
Use percentiles with compliance
Compliance answers whether the contract was met. P50 describes a typical request; P95 and P99 expose the slow tail. Track both because an acceptable average can hide a small but painful group of slow requests.
From a sample to continuous monitoring
This tool evaluates pasted data in your browser and sends nothing to Project Helena. For ongoing checks, Warden stores response time for every monitor, learns its normal P50/P95, and can open a degraded incident when latency remains abnormal.
Need to track this continuously?
Warden records every check, learns a P50/P95 baseline per monitor, and separates slow from down.
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