What Is a Proxy? How Proxies Work and Why

A proxy is a server that sits between you and your destination. Learn how proxies work and why businesses rely on them.

In the context of the internet, IP addresses, scraping, and online automation, a proxy, in its purest form, is a server that sits between you and your destination and forwards your requests on your behalf. The destination sees the proxy's IP, not yours.

That's the whole concept. But to understand why you'd want that, you have to understand the problem proxies solve.

A Real-World Example

Let's say you're a car dealer trying to find used cars at great prices. You don't have the time or the manpower to look through thousands of listings every day across dozens of websites. The natural solution is to build scraping software, a program that acts like a browser, except instead of rendering the data into a user interface, it feeds the data directly into your application.

A well-built scraper lets you maintain a queryable database of cars and their pricing, track when listings are posted, and detect when they get taken off. Now you can sit on top of the entire market instead of refreshing tabs all day.

The Problem With Automated Requests

To defend against DDoS attacks, credential stuffing, and aggressive scraping, websites have implemented detection mechanisms that severely limit automated traffic. They detect bots based on many factors, including browser fingerprint, request patterns, behavioural signals, and TLS fingerprinting (JA3/JA4). But one of the primary factors is still the IP address the requests are coming.

When a website sees an IP making an unusual volume of requests, it'll typically rate limit it by prompting it to solve a captcha, or fully deny it services through a 429/403 status code. Any of those will break the car dealer's scraper, unless he has a way to distribute his requests across many different IPs.

How Proxies Solve It

Once the rate limits start kicking in, the easiest bypass is to route the next batch of requests through a different IP, and your software keeps functioning. Assuming you're also rotating your other identifying signals (browser fingerprint, cookies, TLS profile, etc.), the website sees the new IP as a fresh user with no history. Rate limits tend to be scoped per-IP, so a new IP typically means a fresh budget.

Where Do All Those IPs Come From?

There are several sources, covered in more detail in What Types of Proxies Are There?, but the simplest model is IP leasing. There's an entire marketplace for unused IPv4 address space. Companies that own IP blocks but aren't using them can lease them out to companies that need them.

IPXO is one of the largest platforms built specifically for IPv4 leasing, for outright sales and transfers, IPv4.Global (Hilco) is the most established by volume. Proxy providers like FlashProxy lease pools of IPs on monthly contracts, then sell access to those IPs to their users.

In practice, the car dealer plugs FlashProxy's proxy endpoint into his scraper. Every time his software hits a rate limit on a target website, it rotates to a different IP from the pool. The target sees what looks like thousands of different users browsing listings, instead of one machine hammering the site. The car dealer gets his data, the website doesn't get overwhelmed, and the system works the way it's supposed to.

That's the entire premise of a proxy.

Published by Alon Levi, CEO at FlashProxy

About the author: Alon Levi is the CEO of FlashProxy and has extensive experience in proxy infrastructure, network architecture, and large-scale IP routing technologies.

Connect on LinkedIn · Contact: alon@flashproxy.io

Frequently Asked Questions

What is a proxy used for?

Proxies are most commonly used for web scraping, price monitoring, ad verification, SEO rank tracking, and bypassing geo-restrictions on publicly available data.

Is a proxy the same as a VPN?

No. A VPN encrypts all your device's traffic and routes it through a tunnel. A proxy forwards your requests through a different IP, that traffic can still be encrypted end-to-end (an HTTPS request stays encrypted whether or not it goes through a proxy), but the proxy itself doesn't create a device-wide encrypted tunnel. They serve different purposes.

What is IP rotation?

IP rotation is the practice of switching between different proxy IPs across requests. It prevents any single IP from triggering rate limits on a target website, keeping automated workflows running smoothly.

Do proxies hide your identity?

Proxies mask your real IP address from the destination server, but they do not provide full anonymity. Other signals, such as browser fingerprints, cookies, and TLS profiles, can still identify you without additional precautions.