Bandwidth vs concurrency
Proxy plans have two kinds of limits. Bandwidth is how much data you can move. Concurrency (sometimes called threads) is how many requests you can have open at the same moment. On many plans, concurrency is the limit you'll actually hit, because scrapers spend most of their time waiting for responses.
Rayobyte's rules
At the time of writing, Rayobyte lists:
| Product | Concurrency |
|---|---|
| Premium Residential | Unlimited |
| Scale Residential | 1 concurrent request per $1 of plan |
| Rotating ISP, monthly | 1 concurrent request per $1 of plan |
| Rotating datacenter, monthly | Check plan details; monthly plans are sized by spend |
| Static ISP and datacenter | Per IP; heavy parallel use of one IP risks blocks |
| rayobrowse free tier | 5 browsers at a time |
| Scraping API | Check docs for rate limits on your plan |
So a $500 Scale Residential plan allows 500 requests in flight at once, and a $100 rotating ISP monthly plan allows 100.
How to size your workers
Throughput depends on concurrency and response time:
Requests per second = concurrent requests / average response time in seconds
| Concurrency | Avg response | Requests per second | Pages per day |
|---|---|---|---|
| 100 | 2 s | 50 | About 4.3 million |
| 100 | 5 s | 20 | About 1.7 million |
| 500 | 3 s | 167 | About 14.4 million |
Measure your real response times during a trial, because residential IPs and heavy pages are slower than you'd guess. Our proxy speed test guide shows how.
Staying under the limit
- Use a fixed worker pool sized to your plan's concurrency, rather than spawning a request per URL.
- Put a semaphore or queue in front of the proxy so bursts wait instead of failing.
- Set timeouts. A hung request holds a concurrency slot. 20 to 30 seconds is plenty for most pages.
- Close connections properly, especially in browsers, so slots are released.
- Watch for errors that indicate you've hit the limit and back off.
Residential tip: You can test most of this guide for free: Rayobyte offers a no-card trial on Premium Residential, rotating ISP and rotating datacenter proxies. Move to a paid plan once the pilot works. See our complete Rayobyte guide.
Respecting target limits
Your provider's limit isn't the only one. Targets rate-limit too, and sending 500 concurrent requests to one small site is a fast way to get blocked (and is unfair to the site). Spread concurrency across domains and cap per-domain concurrency. See rate limiting and proxies.
Static IPs and concurrency
On static ISP and datacenter proxies, there's no plan-level concurrency rule, but each IP is one identity. Running 50 parallel requests from one IP to one site looks like a bot. Spread work across the list and keep per-IP concurrency low, a handful of connections at most for sensitive sites.
When to upgrade
If your queue is constantly full and response times are stable, more concurrency will increase throughput linearly. On Scale Residential and monthly rotating ISP plans, that means a bigger plan, which also lowers your per-GB rate. If you need concurrency far beyond your bandwidth needs, ask about enterprise plans, where concurrency can be negotiated separately.
Proxy tip: For a second opinion on hard targets, run the same test through Geonode residential proxies, which support sticky sessions up to 24 hours and ASN targeting. We compare the two in Rayobyte vs Geonode.
How it compares
Webshare plans let you choose a thread count at checkout. Geonode's unlimited residential plans are priced by port speed rather than concurrency. Rayobyte's dollar-based rule is simple to reason about. See Rayobyte vs Webshare pricing and Rayobyte vs Geonode unlimited residential.
For the bigger picture beyond our three partners, read our best proxies buyer's guide, and see cheap proxies for ways to cut cost per successful request.
Budget tip: For jobs where a fixed IP list is enough, Webshare is one of the cheapest options: shared datacenter proxies are sold by the IP, and static residential (ISP) proxies cost well under a dollar per IP per month at the time of writing. More in Rayobyte vs Webshare.
Key takeaways
- Premium Residential concurrency is unlimited; Scale Residential and monthly rotating ISP allow one request per dollar of plan.
- Throughput equals concurrency divided by response time; measure response times in a trial.
- Use a fixed worker pool, timeouts and per-domain caps.
- Keep per-IP concurrency low on static proxies.
FAQ
What happens if I exceed my concurrency?
Extra requests are typically refused or queued. Size your worker pool to stay under the limit.
Does concurrency affect price?
On Scale Residential and monthly plans, concurrency scales with plan price. On Premium Residential, you pay per GB with unlimited concurrency.
Is unlimited concurrency really unlimited?
On Premium Residential, Rayobyte lists it as unlimited. In practice, your infrastructure and targets set the ceiling.
Editorial note: Proxy providers change their pools, features and prices often, so treat any figures here as typical ranges at the time of writing and confirm current terms with the provider before you buy.