Success rate
The share of requests that return a usable response. Meaningless without a sample size and a named target.
Success rate is the proportion of requests that produce the response you wanted. It is the headline metric in proxy marketing and the one most often quoted without the context needed to interpret it.
#What a rate needs to mean anything
- A sample size. “98%” from 100 requests and from 100,000 are very different claims.
- A definition of success. A 200 response containing a block page is not a success, though naive measurement counts it as one.
- A named target. Rates against an echo service and against a heavily defended retailer are not comparable.
- A date. Pools and defences both change continuously.
#The most common measurement error
Counting HTTP status alone. Many anti-bot systems return 200 with a challenge page or an empty result set, because doing so wastes the scraper’s time. Validate that the response actually contains what you asked for, not merely that the request completed.
#Reading provider claims
A rate published without sample size, target and date is marketing. Treat it as a claim about the vendor’s confidence, not as a measurement.