Documentation

How to choose a plan and estimate concurrent connections

Concurrent connections are not the same as the visible thread count in a program. One browser thread can open many connections for images, CSS, JS, APIs and background requests.

Short answer

Choose a plan by the real number of simultaneous network requests, not by the visible thread count in your software. Run a short test, measure peak concurrency, then choose a plan with room to spare.

What you should understand

  • For browser workflows, keep headroom: one tab can create more connections than expected.
  • For scraping-like workflows, count retries, redirects, loaded resources and timeouts, not only threads.
  • If errors appear only under higher load, connection limits may be the issue.
  • A dedicated server makes sense when high limits, speed and control are required.

Symptoms, likely causes and checks

SymptomLikely causeWhat to check
Works at low loadlimit appears under scaleincrease gradually
too many connectionsthreads exceed planreduce parallelism
browser consumes limitmany page resourcesdisable extras or keep headroom
speed dropslimit/geo/proxy typetest nearby plans

SOCKSFIVE settings that are actually relevant here

SettingWhen it mattersWhat to keep in mind
Concurrent connectionsthe key number for multithreaded toolsa browser can create many requests for one page
Speedimportant for media and bulk workflowsdepends on country, IP type and target
Authorized IPswhen using IP authcount how many servers will connect
Dedicated serverfor high continuous loadnot needed for a small manual test

Practical check order

  1. Check basic connectivity and the external IP before the complex workflow.
  2. Change only one parameter at a time: country, type, blacklist or sticky/rotation.
  3. Compare results on the same website, account and test window.
  4. When contacting support, include the exact error text and connection parameters.

Practical example

Concurrent connections are often underestimated because the user sees “10 threads” in software and assumes it means 10 connections. A browser or automation tool can open far more: images, scripts, APIs, redirects and background requests. If errors begin only under load, check actual parallelism rather than country or blacklist first.