IP pools are large sets of exit addresses that a provider assigns to you through a single access point called a gateway. How the service switches those IPs is the key difference covered in the static vs rotating proxies guide.
What is an IP pool
An IP pool is the collection of exit IPs available to you at a given moment or over a period. Bigger and more diverse pools spread traffic across more subnets and ASNs, which helps distribution and reduces repeats.
In practice, providers describe pools either as concurrent supply now or as monthly uniques. Treat huge numbers with caution, because the concurrent count can be far lower than the headline monthly total. Track your own hit frequency and repeat rate to judge usable size.
Gateway endpoints explained
A backconnect gateway is a single hostname and one or more ports that front the entire pool. You connect to that gateway and the service picks or pins the exit IP based on your parameters.
This removes manual IP list management. You do not upload or rotate IPs yourself, you just choose rotation behavior using the endpoint format, session token, or port semantics offered by the provider.
Endpoint formats and parameters
Gateways expose rotation and geo options through hostnames, ports, query strings, or Username fields. The exact syntax varies, but the controls are similar.
Common patterns
| Pattern | Example | What it does |
| Session token in Username | Username: customer1-session-abc123 | Pins one exit for the life of the session token. |
| Session parameter in host | gw.country-us.session=abc123.example.com:10000 | Explicit sticky session tied to a token. |
| Port-based rotation | gw.example.com:10001 sticky, :10000 rotating | Port selects sticky vs rotate or interval length. |
| Query style | gw.example.com:10000?country=DE&session=abc123 | Geo + session in a single endpoint. |
Always check the allowed characters for session tokens and whether tokens expire on inactivity.
Sticky vs rotating sessions
Sticky means the same exit IP remains assigned to a session for its lifetime. Rotating means the gateway changes the exit on each request or at a time interval you picked.
Sticky sessions are usually controlled by a session token in auth or hostname. Rotation can occur per request or after N minutes. If your use case needs persistence for login flows, choose sticky with a known default duration. For high volume distribution, choose rotate by request or by interval.
Pool size and diversity
Usable pool quality is a mix of concurrent size, subnet spread, ASN variety, and freshness. More ISPs and netblocks mean more routes and fewer repeats.
Track: repeat IP rate over time, unique IPs per day, and overlap across threads. If your threads collide on the same subnets, ask the provider about additional ranges or filters.
Network types and typical pool sizes
Different networks have very different pool realities. Datacenter ranges often sit between tens of thousands and a few hundred thousand. Residential vendors advertise millions, but that is usually monthly unique devices rather than concurrent supply. Mobile pools can be small, but CGNAT and trust often offset the size. ISP pools tend to be the smallest and tied to available providers. For a primer on network families, see proxy network type overview.
Geo targeting and uneven distribution
Country or city filters restrict which slice of the pool you draw from. Distribution is uneven by region, with heavy supply in the US and, at times, strong bias to India or other large markets. Confirm country and city depth with your vendor before planning. Learn more in proxy IP geo targeting.
If you need small countries or city level targeting, test for concurrency limits and repeat rate at your target geography. Small pools at city level can exhaust quickly.
Authentication and sessions
Auth can be IP allowlist or Username/Password. When using credentials, the Username often carries the session token and parameters such as country or rotation interval. Keep tokens stable for stickiness and rotate them intentionally when you want a new IP.
Example curl with sticky session
curl -x http://user-country=US-session=abc123:[email protected]:10001 https://ipinfo.io/ip
Replace the parameter style with your provider’s documented format.
Operational tradeoffs: static lists vs backconnect
Static IP lists give maximum control and perfect repeatability, but you must handle rotation, replacements, and health checks yourself. Backconnect gateways automate switching and filtering, which simplifies scaling but hides specific exit details. Choose based on how much control you need vs how much time you want to spend managing lists.
Pricing and plan alignment
Match your plan to how you scale. If you need many concurrent sticky sessions by city, you want pricing that aligns with ports or sessions. If you push volume with fast rotation, per GB or per request models may fit. See proxy pricing models for plan shapes and ceilings.
Quick testing and monitoring
Start with a single thread to validate sticky behavior and default rotation time, then ramp threads while logging exit IPs. Measure unique IPs per minute, repeat ratio, and failure codes at your actual targets. Keep a simple dashboard of recent exits and their ASNs.
FAQs
How do I know if my session is sticky or rotating
Make two requests with the same session token. If the exit IP matches, it is sticky. If it changes, you are on a rotating port or policy.
Why do providers claim 10M or 100M IPs
Those figures are typically monthly unique devices. Concurrent supply at your exact geo and time can be far smaller, which is what matters for throughput.
What defines a good IP pool
Low repeat rate under your load, wide subnet and ASN coverage, and consistent availability at your required geos are stronger indicators than raw headline size.
Is port based rotation better than token based
Neither is strictly better. Tokens offer explicit stickiness and clean lifecycle control. Port semantics are simple for quick switching. Pick the one that matches your tooling.
Do I need city level targeting
Only if your target enforces city checks or you must match user patterns tightly. City slices are smaller, so confirm concurrency and expect higher repeats.