BambuHelper
Cloud Token

Bambu Cloud Setup

Cloud mode connects through Bambu Lab's own MQTT service using an access token from your account. Three ways to put one on the device - sign in on the device itself, let the Companion Tool do it from your PC, or copy the token out of your browser.

When you need this

Only Cloud mode needs an account. LAN mode does not.

  • Use Cloud mode if you would rather not turn on LAN/Developer mode, if the device is on a different network than the printer, or if your printer is cloud-only (P2S).
  • Use LAN mode if the printer and device share a network - it needs the printer's IP and 8-character access code instead, and no token at all.
  • H2 series in LAN mode (H2S, H2C, H2D) needs both LAN-only mode and Developer mode on the printer. If you would rather not enable those, Cloud mode is the way.

Easiest: sign in on the device

Nothing to download, nothing to copy. The device signs in and fetches the token itself.

recommended

Straight from the device's web page

Open your device's page in a browser, go to Printer, set the connection mode to Bambu Cloud, and under Account access choose Sign in with your Bambu account. Two ways in:

  1. Email code - type your account email and press Email me a code. Bambu sends a 6-digit code; enter it. No password is typed at any point.
  2. Password - type your email and password. If the account uses two-factor authentication, the device asks for the second code next: the 6 digits from your authenticator app, or a code Bambu emails you, depending on how your account is set up. Mistyped a code? Just enter it again.

Once signed in, press My printers and pick yours from the account's own list - no serial number to transcribe.

  • Remember the password is optional and only worth ticking if you want the device to renew the token by itself every ~3 months. It works only on accounts without two-factor authentication; with 2FA the device deletes the password the moment it sees the prompt, since it could never finish an unattended sign-in anyway.
  • The device's config page has no password and runs over plain HTTP. Whatever you type into it crosses your network unencrypted. On a network you do not fully trust, use the email code or one of the other two methods - a token expires on its own, a password does not.

From your PC: the Companion Tool

Logs into your account, finds your printers, and pushes the token and serial straight to the device.

One tool, no copy-paste

Useful when you would rather your password never went near the device's plain-HTTP page, or when the device is not reachable in a browser yet.

The tool handles the login (including 2FA), lists the printers on your account, and sends the token plus the matching serial number to BambuHelper over your LAN. Nothing is typed by hand, so there is no way to mistype a serial or truncate a token.

  1. Download BambuHelper-CompanionTool.exe (Windows). On Mac or Linux, run python tools/companion/bambu_companion.py from a clone of the repo.
  2. Run it. Windows may warn about an unsigned tool - choose More info, then Run anyway.
  3. Open Set up a device and sign in with your Bambu account.
  4. Pick your printer, then hit Scan my network to find the BambuHelper - or type its IP if you prefer - and send.

Always download a fresh copy when something stops working. Bambu changes their login flow from time to time, and the fix ships inside the tool.

Manual: copy a token from your browser

The original method, still fully supported. Log into bambulab.com, then read one cookie out of the developer tools.

Open bambulab.com and sign in first - the cookie only exists once you are logged in. Then press F12 and follow the path for your browser.

Chrome / Edge

  1. Open the Application tab (click » if it is hidden).
  2. In the sidebar expand Cookies, then click https://bambulab.com.
  3. Find the row named token.
  4. Double-click its Value cell and copy the whole string.

Firefox

  1. Open the Storage tab.
  2. Expand Cookies, then click https://bambulab.com.
  3. Find token and copy its value.

Safari

  1. Enable the Develop menu first: Settings → Advanced → Show features for web developers.
  2. Open Develop → Show Web Inspector, then the Storage tab.
  3. Expand Cookies → bambulab.com, find token, copy its value.

Then open your device's page in a browser, go to Printer → Cloud, switch Account access to Paste an access token, paste the value in, add the serial number, and save.

The token is long - a few hundred characters. Make sure you copied all of it; a truncated token connects and then silently fails.

Region and serial number

Two settings that quietly break Cloud mode when they are wrong.

  • Server region must match the account - China accounts use a different MQTT host. Europe and the Americas share one host, so the picker offers Europe / Americas and China. A mismatch fails authentication even with a valid token.
  • Serial number is not the printer name. It is a 15-character code like 01P00A000000000, on the printer under Settings → Device or on the label. The name Bambu Studio shows (for example 3DP-01P-110) will not work.
  • Serials are uppercase. The MQTT topics are case-sensitive, so a lowercase serial connects but shows no data.

The device can find the serial for you: My printers lists everything bound to the account once it has a token, and Scan local network finds printers on the same WiFi.

When the token expires

Roughly every three months, and sooner if you sign out everywhere or change your password.

An expired token looks like a printer that will not connect: the device sits on "Connecting", and the Diagnostics page reports an MQTT authentication failure. Nothing is broken - the token simply needs replacing, by any of the methods above.

  • A remembered password renews it for you. If you ticked that box on an account without two-factor authentication, the device signs in again by itself when the broker rejects the old token - you will not notice the expiry at all.
  • Otherwise, signing in again on the device is the quickest fix - the email-code route takes one code and no typing of passwords.
  • Tokens from a sign-in or the Companion Tool tend to last longer than ones lifted from a browser cookie, which can be invalidated as soon as the browser session ends.
  • Nothing on the device needs reflashing - the new token replaces the old one and that is it.

What is stored on the device

The token always. Your email if you signed in. Your password only if you asked for it.

  • The token lands in the ESP32's flash alongside the printer serial, whichever method put it there. It is what talks to Bambu.
  • Your email address is kept after a sign-in, so the page can show which account is connected and so a remembered password has something to pair with.
  • Your password only if you ticked "Remember the password", and then it is stored so the device can renew the token unattended. It is kept in plain text in the ESP32's flash - anyone holding the board can read it. Accounts with two-factor authentication never keep it: the device deletes it as soon as a second factor is demanded.
  • Signing out wipes all three - token, email and password - and drops the live session as well.
  • Read-only. The firmware subscribes to printer status. The only commands it can send are the chamber-light and smart-plug actions you trigger yourself.
  • The Companion Tool keeps nothing - it sends your login to Bambu's own servers and forwards only the resulting token.