# Proxy checker

> Check HTTP, HTTPS and SOCKS5 proxies online: paste up to ten and see which are alive, their exit IP, country and network owner, and the latency.

Source: https://mosaicbrowser.com/tools/proxy-checker

## Proxy checker

Paste up to ten proxies and check each one: whether it is alive, the exit IP it presents, the network that owns it, its country and city, and how long it took to answer. A browser cannot connect through an arbitrary proxy from a page, so this part runs on our server — which keeps no record of what you paste.

**What we keep: nothing.** Credentials are used for that one check and never logged. Use a test credential if your provider gives you one. Private and reserved targets are refused, and there is a limit of 30 proxy checks per hour. The residential-or-datacentre read is a hint from the network owner’s name, not a verdict.

## Alive, and where it exits

A proxy is only useful if it answers and presents the exit you expect. The check completes the real handshake — HTTP `CONNECT` or the SOCKS5 greeting and auth — then reads the exit address through the tunnel, so “alive” means a request actually went out and came back.

### Alive

The proxy answered and tunnelled a request. You get the exit IP, its owner, country and city.

### Auth failed

The credentials were rejected at the handshake — the username or password step for SOCKS5, or a 407 for HTTP.

### Refused / timed out

The proxy did not complete a connection, or did not answer in time. Often a dead host, wrong port or wrong type.

### Exit IP and owner

The address a site would see, and the network behind it. A datacentre owner behind a “residential” claim is a common tell.

1. **Paste your proxies.** Paste up to ten proxies, one per line, in any common format — host:port, host:port:user:pass, or user:pass@host:port.
2. **Check them.** Our server opens a connection to each proxy, completes the HTTP or SOCKS5 handshake, and requests an IP echo through it.
3. **Read the result.** For each proxy you get alive or the step that failed, the exit IP, its ASN and network owner, country and city, and the connect latency.

### Can a website check a proxy from my browser?

No — browsers cannot open a connection through an arbitrary proxy from a page, so this check runs on our server. It opens a socket to the proxy, completes the HTTP or SOCKS5 handshake, and reads the exit IP through it.

### What do the results mean?

Alive with an exit IP means the proxy answered and tunnelled a request. Auth failed means the credentials were rejected at the handshake. Refused or timed out means the proxy did not complete a connection. The country and network owner are read from the exit address.

### Is the residential-or-datacentre label reliable?

Treat it as a hint from the network owner’s name, not a verdict. It is read from the AS organisation behind the exit IP; a provider can sit on networks that do not match the label.

### Are my proxy credentials safe?

They are used only for that one check and are never logged. Still, use a test credential if the provider gives you one. Mosaic itself checks a profile’s proxy before every launch and refuses to open behind one that has not answered.

## Every account its own browser. One price for all of them.

Free holds 3 profiles and 10 profile creations, with no card. Pro is $49 a month for any number, or $490 a year with 2 months free. Try it for 14 days; cancel before day 14 and you pay nothing.

Mosaic is a desktop app

Email yourself the link and open it on your computer.