BambuHelper
Cloud Token

Cloud Token Setup

Cloud mode connects through Bambu Lab's own MQTT service using an access token from your account. Two ways to get one - a tool that does it for you, or a copy-paste from your browser.

When you need a token

Only Cloud mode uses one. 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: the Companion Tool

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

recommended

One tool, no copy-paste

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 the token from your browser

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, paste the value into Access token, 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 the token came from - China accounts use a different MQTT host than US/EU. A mismatch fails authentication 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 also find the serial for you: on the Cloud tab, use Scan local network when the printer is 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, using either method above.

  • Tokens from 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 - paste the new token over the old one and save.

What is stored on the device

The short version: the token, and nothing else.

  • No account credentials. BambuHelper never asks for your email or password. The Companion Tool sends your login to Bambu's own servers and keeps nothing.
  • Only the token lands in the ESP32's flash, alongside the printer serial.
  • Read-only. The firmware subscribes to printer status. The only commands it can send are the chamber-light controls you trigger yourself.