What is Endpoint?
A proxy endpoint is the address a client dials to reach a proxy, a hostname or IP plus a port, usually with credentials attached. Written as host:port, it is the single string you paste into a browser, scraper or antidetect profile. One endpoint can map to one fixed device or to a whole rotating pool.
An endpoint is normally written as a URL: scheme://username:password@host:port. The scheme decides which protocol the client speaks, http:// for an HTTP proxy and socks5:// or socks5h:// for SOCKS. That trailing h is worth knowing, because in curl and in Python's requests it tells the client to hand the hostname to the proxy for resolution instead of resolving locally, which is the difference between a clean exit and a DNS leak. Some tools want the same parts in separate fields rather than one string.
Endpoints come in two shapes. A dedicated endpoint points at one device or one fixed exit and keeps that address until you rotate it. A backconnect gateway endpoint is a single hostname and port fronting an entire pool, where each connection can leave from a different address and you steer country, carrier or session length with parameters embedded in the username. The string you configure never changes while the exit IP behind it does, which is what makes gateway credentials easy to hardcode and hard to audit.
Treat an endpoint as a credential. It carries a username and password that work from anywhere unless the provider also restricts by source IP, so it belongs in an environment variable or a secret store rather than in committed code, and rotating a password should never require a code change. Where a provider bills per endpoint, the count becomes a budget question; PROXIES.SX does not charge for endpoints and bills bandwidth alone, so how many you create is an operational choice rather than a line item.
Errors point at specific layers. A 407 response with a Proxy-Authenticate header means the endpoint was reached and the credentials were refused or missing. A refused connection means the port is wrong or the listener is down. A connection that opens and then stalls on the first request usually means the client spoke the wrong protocol to that port, HTTP to a SOCKS listener or the reverse. If everything connects but the exit lands in the wrong country, check the parameters in the username.
Where you meet it
You copy an endpoint out of a dashboard and paste it into Scrapy settings, a Puppeteer launch flag, an antidetect browser profile or a curl command. The choice it forces is between one gateway endpoint that rotates on every request and a set of fixed endpoints you can pin a logged-in session to. Getting that wrong shows up weeks later as accounts that keep being logged out.
Common questions
What is the difference between a proxy endpoint and a proxy IP?
The endpoint is the address you connect to; the proxy IP is the address the destination site sees. With a single fixed proxy they can be the same machine. With a rotating gateway, one endpoint hostname stays constant while the exit IP changes on every request or every session.
How many proxy endpoints do I need?
Count concurrent identities rather than requests. Every browser profile or logged-in account that must keep a stable address needs its own sticky endpoint or session token. Stateless scraping can push thousands of requests through a single rotating gateway endpoint, because the pool behind it supplies the addresses.
Why does my proxy endpoint return 407?
HTTP 407 with a Proxy-Authenticate header means the proxy was reached and rejected your credentials. Common causes are a password that was not URL-encoded inside the endpoint string, a client that strips credentials when following a redirect, or IP authentication set for an address you are no longer connecting from.
Related terms
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