Glossary · Performance
Success rate
The share of requests that come back with the data you wanted, the metric that actually measures a proxy's worth.
Success rate is the fraction of requests that return the intended result rather than a block, a CAPTCHA, an error or an empty page. It is the number that matters most and the one advertised least, because it depends on the hard, changing reality of how a target treats your traffic, not on a headline pool size.
It is also where cheap proxies reveal their true cost. A pool of tainted addresses might quote a low price per gigabyte, but if half the requests fail you pay for the failures too, in wasted traffic and in retries, so the effective cost per successful result is far higher than the sticker.
The right way to compare proxies is therefore to measure success rate against your actual targets, not to compare pool counts or per-gigabyte rates in the abstract. A clean pool with a high success rate beats a huge one with a low one at almost any price.
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