What is a proxy?
- A proxy replaces your IP address. It does not encrypt your traffic — that is what a VPN is for.
- There are four types: residential, datacenter, ISP and mobile. Trust and cost move in opposite directions to speed.
- Websites classify your IP in a single ASN lookup, which is why datacenter proxies fail on strict sites.
- Rotate for broad crawling; hold a sticky session for anything involving a login or a cart.
- Residential and mobile are billed by bandwidth, so what you download matters more than how many pages you visit.
Think of a mail forwarding service. You post a letter to them, they put it in a new envelope with their own return address, and send it on. The recipient replies to that address, and the company forwards it back to you. They never learn your home address — and neither does the person you wrote to.
Flip the proxy on and off — watch which IP address arrives at the far end.
- Your traffic, relayed by the proxy
- Direct route — unused
The site never learns your address.
It sees the proxy’s IP, its location and its reputation. Note that a plain proxy swaps the address — it does not encrypt the traffic on the way there.
How a proxy request actually works
- STEP 1
Your app sends the request to the proxy
Instead of dialling the website directly, your browser or script is configured to hand every request to the proxy first.
- STEP 2
The proxy opens its own connection
It contacts the target site using its own IP address. As far as the site is concerned, the proxy is the visitor.
- STEP 3
The site replies to the proxy
The response is addressed to the proxy, carrying whatever content that IP and location are entitled to see.
- STEP 4
The proxy hands it back to you
You get the page. Your own address never appeared in the conversation.
Proxies are graded by what they disclose. These are the actual HTTP headers that arrive at the server.
No proxy headers at all. From the headers alone this is indistinguishable from a direct connection — the baseline you want.
Elite only covers headers. The ASN check above still applies — an “elite” datacenter proxy is simply a datacenter proxy with good manners.
The four proxy types
IPs issued by consumer ISPs to actual households. Because blocking one risks blocking a genuine customer, defended sites treat them far more gently than anything from a data centre.
Strict targets, geo-accurate pricing, account work, retail and travel sites
Billed per GB and noticeably slower — a heavy page can cost real money.
How websites detect proxies
Every IP belongs to a network with an ASN. That single lookup reveals what kind of connection you are on.
Flagged — challenge or block
Registered to a hosting company. Ordinary shoppers do not browse from cloud servers, so this is treated as automation before a single page loads.
This is why a datacenter proxy fails on strict sites no matter how clean its headers are — and why residential IPs cost more. You are paying for the ASN, not the bandwidth.
Rotating vs sticky sessions
Watch which IP each request goes out from — and what breaks when it changes mid-flow.
Rotating: a new IP on every request
Perfect for broad, stateless crawling — thousands of pages spread across thousands of addresses. But notice the logins and checkouts failing: to the server, the user teleported mid-transaction.
Most providers deliver rotation through a backconnect gateway — one endpoint that hides a pool of millions behind it, configured through the username.
HTTP vs SOCKS5
HTTP / HTTPS proxies
Understand web traffic specifically. Because they can read the request, they can cache responses, filter by URL and modify headers. That makes them the default for browsing and scraping, and the reason corporate networks use them for logging.
SOCKS5 proxies
Move packets without interpreting them, so they carry any protocol — email, torrents, games, custom TCP. Lower overhead and more flexible, but no caching or content filtering, because they never look inside.
Full breakdown in HTTP, HTTPS and SOCKS5 proxies compared.
Proxy or VPN?
- Swaps your IP, no encryption by default
- Usually applies per application
- Gives you thousands of addresses on demand
- Billed per GB or per IP
Best for scraping, multi-accounting, geo-testing at scale.
- Encrypts everything leaving your device
- Covers the whole system
- One shared IP per server
- Flat monthly subscription
Best for privacy, public Wi-Fi, streaming from abroad.
Learn the other side in our VPN lesson or read proxy vs VPN.
What proxies actually cost
Residential proxies bill by traffic, not by request — so page weight drives the bill more than page count.
Block images and fonts and you would save about 98 GB — roughly $244–$684 a month.
Indicative street pricing, not a quote — rates fall sharply with volume commitments. Datacenter and ISP proxies are often sold per IP rather than per GB, so treat those figures as an equivalent.
Six things that actually matter
Success rate on your targets
Not pool size. A cheap IP that gets blocked is expensive once retries and failed jobs are counted. Always trial against the sites you actually scrape.
Test a proxyThe right IP type
Paying residential prices for an undefended target wastes budget; using datacenter IPs on a strict one wastes time. Match the type to the defence.
Compare proxy typesGeo-targeting granularity
Country level is the baseline. City and ISP targeting matter for local SEO, ad verification and region-specific pricing.
Proxies by countryRotation and session control
You want both: per-request rotation for broad crawls, and sticky sessions with a controllable duration for anything stateful.
Backconnect gatewaysHow the IPs were sourced
Ethically built residential pools are more stable and carry less compliance risk. It is a fair question to ask a provider directly.
Where residential IPs come fromPricing that matches your shape
Per-GB suits bursty work; per-IP suits steady long-lived sessions. Model your real volume before committing to a plan.
Cheapest optionsFive expensive mistakes
- 1
Buying on price per GB alone
A $2/GB pool with a 40% block rate costs more per successful request than a $5/GB pool that works. Measure success rate, not headline price.
- 2
Rotating IPs mid-session
Logins, carts and checkouts break when the address changes halfway through. Use sticky sessions for anything stateful.
- 3
Downloading everything
Images, fonts and video are billed the same as the data you actually want. Blocking assets routinely cuts residential bills by 60–80%.
- 4
Blaming the proxy for every block
IP reputation is one signal. Headers, TLS fingerprint and request timing matter too — a perfect IP behaving like a bot still gets caught.
- 5
Using free proxy lists
Slow, already blocklisted, and operated by people you cannot identify. Fine for a throwaway test, never for anything with credentials.
Test yourself
1A website can tell your datacenter proxy apart from a home connection even with perfect headers.
2You need to log in, add to a cart and check out. Which do you use?
3Residential proxies are usually billed by…
4Which proxy type is hardest for a website to block outright?
5Does a plain proxy encrypt your traffic?
Proxy FAQ
1What is a proxy server in simple terms?
A proxy is a computer that sits between you and the website you are trying to reach. Your request goes to the proxy, the proxy forwards it using its own IP address, and the reply comes back the same way. The website records the proxy’s address rather than yours.
2What is the difference between a proxy and a VPN?
A proxy swaps your IP address, usually for a single application, and does not encrypt your traffic by default. A VPN encrypts everything leaving your device and covers the whole system. Use a proxy when you need many different IPs; use a VPN when you want privacy and encryption.
3Which proxy type should I choose?
Match it to how well defended your target is. Datacenter proxies for open pages and APIs where speed and cost matter. Residential for strict sites and anything location-sensitive. ISP when you need one fast, stable, trusted identity. Mobile for social platforms and the hardest targets.
4Why do my datacenter proxies keep getting blocked?
Because a single ASN lookup shows the address belongs to a hosting company rather than a consumer ISP, and real shoppers do not browse from cloud servers. No amount of header cleaning fixes that — you need residential or mobile IPs for those targets.
5What does rotating a proxy actually mean?
A rotating proxy gives you a different IP on each request, which spreads a large job across many addresses and keeps simple rate limits at bay. A sticky session holds one IP for a set period, which is what multi-step flows like logins and checkouts need.
6How much do proxies cost?
Residential and mobile proxies are billed per GB of traffic, so cost scales with page weight rather than page count — expect roughly $2.50–$7 per GB for residential and more for mobile. Datacenter and ISP proxies are usually sold per IP and are far cheaper.
7Are free proxies safe to use?
Generally no. They are slow, overcrowded and frequently already blocklisted, and you have no idea who operates them or what they do with the traffic passing through. Never send logins or personal data through a free proxy.
8Is using a proxy legal?
Yes, proxies are ordinary networking tools used every day by businesses for filtering, testing and data collection. What matters is what you do with one — respect each site’s terms of service and follow data-protection law for anything personal you collect.