Full definition
A provider's IP pool is the count of unique IPs you can rotate through. Bigger isn't automatically better — what matters is fresh IPs (how often the pool rotates), and clean IPs (none of them are pre-burned by other scrapers). A 100M IP pool that's 80% reused stale IPs is worse than a 10M pool of fresh IPs.
Common pool size claims: Bright Data 150M+, Oxylabs 177M+, Smartproxy 115M+, IPRoyal 32M+. These numbers are aggregated over the lifetime of the network — the *active concurrent* pool is much smaller, typically 1–5% of the claimed total at any moment.
What to look for: providers that publish "pool freshness" or "IP refresh rate" — Bright Data and Oxylabs publish these in their methodology. ProxyLook's methodology page explains how we measure pool freshness independently across 7-day windows.