Migrate Undetectable to JustBrowser: Profiles, Cookies, Proxies (2026)

Last Tuesday at 2am, I watched a guy in our Discord export 73 browser profiles from Undetectable. One by one. He'd been putting off the migration for three months because "it seemed complicated." By 5am he was done. All profiles running in JustBrowser, all sessions intact, zero accounts flagged.

His words afterward: "Why did I wait so long?"

That's the thing about antidetect browser migrations — they feel scarier than they are. You've got sessions logged in, cookies warm, proxies bound. Any mistake will torch everything, right? Nah. The actual process is file exports and re-imports. Methodical work, not rocket science. (I say this having personally screwed up a migration in 2024 by forgetting to document proxy credentials. Spent four hours re-authenticating accounts. Learn from my mistakes.)

By the end of this guide, you'll have your Undetectable profiles running in JustBrowser with cookies preserved, proxies rebound, and fingerprints verified against CreepJS and FingerprintJS Pro. We'll cover the export process, the import mapping, and the verification steps that confirm nothing broke.

Prerequisites

Before starting, make sure you have:

Undetectable installed with the profiles you want to migrate
JustBrowser installed — 7-day trial gives you unlimited profiles to test the migration process before committing
Proxy credentials documented — host, port, username, password for each profile's proxy (Undetectable doesn't always export these cleanly)
30-60 minutes for a small batch (under 10 profiles), 2-3 hours for larger migrations

No coding required. If you want to automate bulk migrations later, JustBrowser's REST API handles that — but start manual for your first batch. Seriously. I've seen people try to script their first migration and blow two days debugging edge cases they would've caught in 20 minutes of manual work.

Step 1: Export Profiles from Undetectable

Open Undetectable and locate the profiles you want to migrate. You have two export options:

Option A: Full profile export (recommended for most users)

Right-click a profile and select "Export Profile." Undetectable creates a .profile file containing:

Browser fingerprint configuration
Cookies (in JSON format)
Local storage data
Some extension data (varies by version)

Save these files somewhere organized — I use a folder named undetectable-export-2026-07 with subfolders per profile.

Option B: Cookies-only export (for simpler migrations)

If you only need to preserve logged-in sessions, go to the profile's cookie manager and export cookies as JSON. This is lighter but means you'll recreate fingerprint settings manually.

What doesn't export cleanly:

Proxy credentials. Undetectable stores them, but the export format varies between versions. Before exporting, open each profile's proxy settings and copy the credentials to a separate document. Host. Port. Username. Password. Proxy type (HTTP, SOCKS5). You'll need these for Step 3.

Also: browser extensions with external accounts (like password managers) need re-authentication in JustBrowser. The extension files might transfer, but OAuth tokens won't. This is annoying. I wish there was a workaround, but there isn't — extension auth is sandboxed for good reason.

Step 2: Create Matching Profiles in JustBrowser

Now for the JustBrowser side. You're essentially recreating each profile with matching fingerprint parameters, then importing the cookies.

Open JustBrowser and create a new profile. Match these settings to your Undetectable export:

Fingerprint settings:

OS: Match exactly — if your Undetectable profile was Windows 11, use Windows 11
Screen resolution: Same as before. Changing from 1920x1080 to 2560x1440 during migration is a fingerprint change that platforms might notice
Timezone: Must match your proxy location. German proxy = Europe/Berlin
Language: Same as before. Don't "improve" from en-US to de-DE unless your proxy also changed
WebGL/Canvas/Audio: JustBrowser auto-generates these to be hardware-consistent. For most migrations, let it auto-generate fresh values rather than trying to replicate exact old values

Why not copy exact fingerprint values?

Here's a counterintuitive thing: you don't want byte-identical fingerprints. If your Undetectable canvas fingerprint is literally identical to your JustBrowser canvas fingerprint (which it won't be unless you're doing manual hex editing), that itself is suspicious. What matters is consistency within the session — not replication across browsers. Fresh fingerprints in JustBrowser, imported cookies, same proxy IP. That's the combination that works.

The exception: if you had custom hardware spoofing (specific GPU strings, specific screen dimensions for unusual monitors), replicate those. But canvas/audio/WebGL hash values? Let them regenerate.

Honestly, this "don't copy exact fingerprints" thing trips people up constantly. The instinct is to preserve everything. But fingerprints aren't passwords — they're supposed to look real, not identical across browsers. A human using two different computers has two different canvas fingerprints. That's normal. What's suspicious is two browsers producing byte-identical hashes when they shouldn't. We covered the technical details in our WebGL fingerprinting deep dive.

For profiles that manage ad spend — Google Ads accounts, Facebook Business Manager — you'll want click fraud protection running too. Different tool, same workflow. Helps when the accounts you're migrating are burning real money.

Step 3: Import Cookies

This is where sessions get preserved. If cookies import correctly, you won't need to re-login to anything.

In JustBrowser, open your new profile and go to the cookie manager:

Click "Import Cookies"
Select the JSON file from your Undetectable export (or the .profile file if JustBrowser's importer handles it — check current version docs)
Review the imported cookies — look for the domains you care about (amazon.com, facebook.com, whatever)
Save and close

If cookies aren't in a compatible format:

Some Undetectable versions export cookies in Netscape format or a proprietary format. Use a converter — there are free online tools that convert between cookie formats. Convert to JSON, then import.

Session expiration warning:

Cookies have expiration dates. If you exported a profile a week ago and some cookies were set to expire in 5 days, those sessions are gone. Export and import on the same day. I've seen people export profiles "to migrate later" and then wonder why half their sessions are dead three weeks later. The cookies expired. That's all. No conspiracy. Just calendar math.

Step 4: Rebind Proxies

Remember those proxy credentials you documented in Step 1? Time to use them.

In each JustBrowser profile, go to Proxy Settings:

Type: HTTP, HTTPS, or SOCKS5 — match what you had in Undetectable
Host: Your proxy server address
Port: Usually 3128, 8080, or whatever your provider assigned
Username/Password: Enter exactly as documented

Test the proxy before saving. JustBrowser shows:

IP address
Country/city geolocation
ISP name
IP type (residential, ISP, datacenter)

Verify this matches what you expected. If your Undetectable profile used a German ISP proxy and JustBrowser shows a US datacenter IP, something's wrong with your credentials or you're on the wrong proxy product.

Sticky session consideration:

If you were using session-sticky proxies in Undetectable (Bright Data's -session-xxx parameter, for example), recreate the same session ID in JustBrowser. This ensures you get the exact same IP. Different session ID = different IP = platform sees a location change = potential flag.

For ISP proxy setup details, we covered the full configuration in our ISP proxy tutorial.

Step 5: Verify Fingerprint Integrity

Before using migrated profiles for anything important, run fingerprint checks.

Open the JustBrowser profile and visit:

CreepJS — look for red flags on consistency checks
Pixelscan — verify IP/timezone/language alignment
BrowserLeaks — check individual fingerprint components

What you're looking for:

No timezone mismatches (profile timezone matches proxy geolocation)
No language inconsistencies (browser language matches expected user region)
WebGL and canvas fingerprints are internally consistent (not flagged as spoofed)
IP checks pass — not on known blacklists, correct country/city

If something fails:

Most failures come from three issues:

Timezone mismatch: Edit the JustBrowser profile, fix the timezone to match proxy location
Language mismatch: Edit profile, adjust primary language
WebGL shows impossible hardware: Regenerate the fingerprint (let JustBrowser create a consistent set)

Don't skip verification. I know it adds time. I know you're already tired of the migration process. Do it anyway. One failed fingerprint check is better discovered now than after your account gets flagged. For a full walkthrough of CreepJS testing, see our CreepJS antidetect verification guide.

Step 6: Test on a Low-Stakes Account

Before pointing your most valuable accounts at these migrated profiles, test with something expendable.

Pick one migrated profile. Log into a platform where you have a throwaway account — buyer account instead of seller, personal Facebook instead of Business Manager admin. Use it normally for 24-48 hours. If it survives without flags, your migration is clean. If something gets flagged, debug that profile before migrating high-value accounts.

Common Errors and How to Fix Them

Cookies imported but sessions are logged out

Cause: Cookie format mismatch, or cookies expired before import.

Fix: Re-export fresh cookies from Undetectable immediately before importing. If format issues persist, use a cookie format converter (Netscape to JSON, etc.).

Proxy authentication failed in JustBrowser

Cause: Credentials copied incorrectly, or special characters in password need URL encoding.

Fix: Double-check credentials against your provider's dashboard. If the password contains @, #, or other special characters, try URL-encoding them or resetting to an alphanumeric-only password. Our timezone and geolocation spoofing guide covers the proxy/location alignment issues in detail.

Fingerprint checker shows timezone/language mismatch

Cause: Profile settings don't match proxy location.

Fix: Edit the JustBrowser profile. Set timezone to the proxy's geographic timezone (US-East proxy = America/New_York, German proxy = Europe/Berlin). Set primary language to match the locale.

Account flagged after migration

Cause: Multiple possibilities — IP change during migration, fingerprint inconsistency, or just bad timing with platform's security sweep.

Fix: Check if your proxy IP stayed consistent between Undetectable and JustBrowser. Run CreepJS and Pixelscan again. If everything looks clean, wait 24-48 hours — some flags are temporary security checks that clear themselves. If the account stays restricted, the issue predates your migration (or the migration exposed an existing weakness). Sometimes there's nothing you did wrong. Platforms flag accounts for reasons they never explain. Frustrating? Absolutely. Fixable? Not always. For Facebook-specific issues, our Facebook Business Manager fingerprinting guide covers the common detection vectors.

For analytics on how accounts perform post-migration, JustAnalytics tracks conversion without feeding data back to the platforms you're isolating.

Next Steps

Once migration is complete, you've got access to JustBrowser's full feature set — cookie warm-up across 127 curated sites, profile aging, REST API + CDP for Playwright/Puppeteer/Selenium automation, and unlimited cloud sync on Pro to backup your profiles.

For comparison between JustBrowser and other antidetect tools, we wrote a detailed Multilogin comparison and a GoLogin comparison.

The 73-profile guy from the intro? Six months into JustBrowser now, hasn't looked back. One night of migration work, unlimited profiles at $9.99/month instead of paying per-profile. Do the math on your own account count.

(If you're wondering why I'm so bullish on JustBrowser specifically — yeah, I work here. But I also migrated my own personal profiles after testing four different antidetect tools. The native Chromium engine matters. Extension-based fingerprint spoofing leaks in ways that get your accounts banned. Learned that the expensive way.)

More operational guides on the JustBrowser blog.

Frequently Asked Questions

Will I lose my logged-in sessions when migrating from Undetectable to JustBrowser?

Not if you export cookies properly. Undetectable exports cookies in JSON format, which JustBrowser imports directly. As long as you transfer cookies before they expire and keep the same proxy IP, most platforms maintain the session. We've seen users migrate 50+ profiles with zero re-logins required.

Can I migrate Undetectable profiles with active proxy bindings?

Yes, but you'll need to rebind proxies manually in JustBrowser. Export your proxy credentials from Undetectable (host, port, username, password), then add them to each JustBrowser profile. The proxy itself doesn't care which browser uses it — only the account sees the IP.

How long does migrating from Undetectable to JustBrowser take?

For a single profile, about 5-10 minutes including fingerprint verification. For bulk migration (20+ profiles), expect 2-3 hours if you're methodical. The export from Undetectable is fast; the import and verification in JustBrowser takes the time.

Does JustBrowser support the same fingerprint parameters as Undetectable?

JustBrowser covers 40+ fingerprint parameters including canvas, WebGL, audio, fonts, screen, timezone, and navigator — more than Undetectable's default set. You won't lose fingerprint coverage. Some parameter names differ between tools, so manual mapping is needed for custom fingerprint configs.

Try JustBrowser

Native Chromium antidetect browser — not extension-based. Real C++ engine patches at the canvas / WebGL / font / TLS layer, so 40+ identity parameters are genuine, not faked. REST API for Playwright, Puppeteer, Selenium. 7-day free trial, card required — then $9.99/month or $99.99/year, unlimited profiles, free team seats.

Get started → · How it differs from Multilogin / GoLogin / AdsPower