A thread limit is the maximum number of simultaneous connections or requests a proxy plan allows a user to run at the same time. Once this limit is reached, additional requests must wait or get rejected until a slot frees up.
Each proxy plan is configured with a set number of concurrent threads the account can use across its proxy pool. When a scraping tool sends more simultaneous requests than the plan allows, the extra requests are queued or blocked by the provider system. Users running large scraping or automation jobs need to match their tool settings to the plan thread limit to avoid errors. Higher-tier plans typically offer higher thread limits to support larger, faster jobs.
This is largely a plan and configuration choice, not a technical limitation.
USER-thread-limit-session-task01Everything lives in the username -- add "thread-limit" to any proxy credential to apply thread limit to a single task. Swap "task01" for a new label to spin up an independent, isolated identity.
KnoxProxy sticky sessions persist up to 30 minutes on residential (60 on mobile), and the window refreshes with activity.
Each session or connection label gets its own exit, so parallel identities never collide.
This costs nothing beyond bandwidth -- successful responses are billed, not the session or connection itself.
Run as many parallel sessions or connections as the job needs -- concurrency is not capped on any plan.
A scraping tool configured to run 200 threads at once will hit errors on a proxy plan that only allows 50 concurrent connections.
Matching thread limits to actual project needs prevents wasted spend on unused capacity or frustrating bottlenecks during large jobs. Understanding this setting helps buyers pick the right plan size for their workload.
Extra requests beyond the limit are typically queued or rejected with an error. They wait until existing connections finish and free up capacity.
Estimate how many pages or requests you need to process per minute. Match that number to a plan with enough concurrent thread capacity to avoid slowdowns.
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