Undetectable.io with USA Mobile Proxies: A Plain Setup Guide

Undetectable.io is an antidetect browser for Windows and macOS. Each profile you build in it carries its own fingerprint and its own proxy, so several browser identities can live on one computer without sharing cookies, storage or a device signature. What the browser cannot invent is a believable network address. Leave the proxy field empty and every profile walks out through the same office or home connection, which quietly ties them all back together. That gap is what we fill. BetterProxies runs its own 4G and 5G modems with real SIM cards on AT&T, T-Mobile and Verizon, and each line you buy is yours alone. This guide goes field by field through attaching one of our lines to an Undetectable.io profile, explains when to keep an IP and when to change it, and lists the handful of mistakes we see most often. No fine print, no surprises.

What Undetectable.io handles and what the proxy handles

Think of a profile as two halves. Undetectable.io looks after the device half: the fingerprint, the cookie jar, local storage and the browser history that belong to that profile and nobody else. The proxy looks after the network half: the IP address a website sees, and with it the carrier, the city and the time zone that address points to. A profile only reads as one coherent person when both halves agree.

Undetectable.io gives you two kinds of profile. Local profiles are stored on your own device. Cloud profiles live in your account and can be opened from another computer, which is handy if you switch between a desk machine and a laptop. The free plan lets you start with up to 5 cloud profiles, and paid plans raise that number when you need more. Either kind takes a proxy in exactly the same way.

Every BetterProxies line comes with the values the profile asks for: a host, an HTTP port, a SOCKS5 port, a username and a password, plus a rotation link. You will find all of them on the proxy row in your dashboard. If you prefer not to use a password, you can whitelist your own IP instead, though for an antidetect browser the login and password route is usually tidier.

Adding a BetterProxies line to a profile, step by step

Keep your BetterProxies dashboard open in one window and Undetectable.io in another. Copying values straight across, rather than typing them, avoids nearly every first-run problem we are asked about.

1. Create a new profile in Undetectable.io, or open the settings of one you already have.
2. Go to the proxy part of the profile settings and choose the type: HTTP for everyday browsing, SOCKS5 if the profile needs it for a particular tool.
3. Copy the host from the dashboard, then the port that belongs to the type you picked. The HTTP and SOCKS5 ports are different numbers.
4. Paste the username and the password from the same dashboard row.
5. Run the proxy check. A working line comes back with a US carrier IP in the metro you bought.
6. Save the profile, open it, and load any IP lookup page to see the same address from inside the browser.

• Type and port must match; a SOCKS5 port under an HTTP type fails every time.
• Paste credentials so no trailing space sneaks in.
• One line per profile, written down next to the profile name so you always know which is which.

Keep the profile's story consistent

A carrier IP in Phoenix paired with a profile that claims to be in London on London time is a contradiction websites notice. Let the time zone, the language and the geolocation of the profile follow the proxy IP rather than setting them by hand. When the proxy changes city, those values should change with it.

WebRTC deserves the same attention. Set it so the profile shows the proxy's IP, never your local address. This is the setting most often left at a default that leaks the real connection, and it is worth checking on every new profile before it touches an account.

Our hardware sits in eight US metros: New York, Los Angeles, Chicago, Houston, Phoenix, Miami, North Carolina and Boston. Naming profiles by metro, for example Chicago 01 and Chicago 02, keeps the IP, the time zone and the account history lined up without anyone needing to remember it.

Sticky sessions, rotation and when to use each

A BetterProxies line can hold one IP for as long as you like, which we call a sticky session. That is the right mode for nearly every Undetectable.io profile. An account that signs in today and again tomorrow should look like it is on the same phone network, not on a new address every few minutes.

When you do want a fresh IP, open the rotation link for that line or call it through the API. Host, port and login stay exactly as they are, so the profile needs no editing. Close the profile before you rotate and reopen it afterwards, so the browser starts its session on the new address rather than switching halfway through a page.

Good moments to rotate are between tasks, when you retire a profile, or before giving a line to a brand new identity. Bad moments are any time a profile is logged in and active. If a teammate keeps the rotation link in a script, make sure the script never runs against a profile somebody is using.

Growing from a few profiles to many

The habit that keeps a larger setup healthy is simple: one proxy per profile, or at most one proxy per small group of profiles that never touch the same platform. Sharing a single IP across accounts on the same site links them, and that undoes the isolation Undetectable.io works to create.

On paid plans Undetectable.io can import proxies in bulk, which saves time once you have more than a handful of lines. On its bigger plans, profiles can be shared with team members, so a colleague can open a profile with the proxy already attached. Each BetterProxies line keeps its own credentials, so moving one person off a project does not disturb anybody else's profiles.

If you need a line in a different metro later, ask us and we move it. After the move, run the proxy check in the profile again so the time zone and location refresh to the new city.

Fixing the usual problems

If the proxy check fails with an authentication error, re-copy the password and confirm the port belongs to the type you selected. Those two causes cover almost every failed check.

If the check passes but a website shows your home IP, look at WebRTC first, then make sure no browser extension inside the profile is routing traffic around the proxy.

If the time zone looks wrong, the profile was probably set up by hand before the proxy was added. Switch those fields back to following the IP and open the profile again.

If an account was logged out mid-session for no obvious reason, check whether the rotation link was called while the profile was open. Rotating between sessions instead of during them fixes this for good.

Getting Undetectable.io, and the alternative

Undetectable.io is the browser we suggest first for BetterProxies customers on Windows or macOS. The free plan is enough to try a couple of profiles with one of our lines before you commit to anything larger.

If you also need Linux, or want to open profiles from an Android or iOS phone, GoLogin is the alternative we point people to. It takes our lines the same way: host, port, username and password per profile.

• Get Undetectable.io (partner link)
• Get GoLogin (partner link)

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