How to Turn On Developer Mode on a Chromebook (and What You Lose)

What does developer mode do on a Chromebook?

Developer mode gives you root-level access to ChromeOS: a Linux shell with superuser privileges, the ability to boot from USB or install a custom OS, and support for loading unpacked (unpublished) Chrome extensions on devices that otherwise block it. It does this by turning off verified boot, ChromeOS's normal check that only Google-signed software runs at startup.

Most people never need it. It exists for developers testing extensions or web apps, people running alternative Linux setups, and anyone who needs the crosh shell's deeper commands. If you just want Linux apps through the standard Linux (Beta) feature, or to load a normal extension, you don't need developer mode at all; that support is handled separately in ChromeOS Settings and Chrome's own extensions page.

How do you turn on developer mode on a Chromebook?

You enable it from ChromeOS's recovery screen, not from a Settings menu, and the process forces a full data wipe as part of the switch.

1. Back up anything stored locally to Google Drive or another device; this process erases the device.
2. Turn off the Chromebook completely.
3. Hold Esc + Refresh (the circular arrow key) and press the Power button to enter recovery mode.
4. At the screen reading that Chrome OS is missing or damaged, press Ctrl + D.
5. Press Enter, or follow the on-screen prompt on some models, to confirm turning on developer mode; the device reboots and Powerwashes automatically.
6. Wait through the reboot, which can take several minutes and leads into a warning screen from then on.

What do you lose when you turn on developer mode?

Turning it on Powerwashes the device immediately: every local file, downloaded app, and saved login not synced to your Google account is gone, and you start from the out-of-box setup screen again.

• Local files not backed up to Drive or an external drive.
• Any Android or Linux apps and their local data.
• Offline-only browser extension data that wasn't synced.
• Saved Wi-Fi passwords and device-level settings not tied to your Google account.

Everything tied to your Google account, including bookmarks, extensions installed through the Web Store, and browsing history if sync is on, comes back once you sign in again after the Powerwash, the same as setting up a new Chromebook.

What is verified boot, and why does developer mode disable it?

Verified boot, also called OS verification, checks every time you start the Chromebook that the operating system hasn't been modified and matches Google's signed image. Developer mode turns this check off so you can run your own code, which is also why every boot afterward shows a warning screen.

Once developer mode is on, you'll see a screen reading that OS verification is off, with a beep, every time you start the device. Pressing Ctrl+D, or waiting a few seconds, boots normally; pressing Space at that screen instead re-enables verification, which triggers another Powerwash. Chromium's own verified boot design documentation covers the technical details if you want the full picture.

How do you load an unpacked extension once developer mode is on?

Loading an unpacked extension uses Chrome's own extensions-page toggle, which works the same on a Chromebook in developer mode as on Windows or Mac. You don't need ChromeOS developer mode just for this on most current Chromebooks, though some managed devices block unpacked loading unless the OS-level developer mode is also on.

1. Go to chrome://extensions.
2. Turn on Developer mode using the toggle in the top-right corner.
3. Click Load unpacked.
4. Select the folder containing your extension's manifest.json.
5. The extension appears in your toolbar immediately, without needing the Chrome Web Store.

This is the main developer-facing reason people look up ChromeOS developer mode at all: testing an extension you're building before publishing it. Chrome's extension development guide walks through building one from scratch, and for the standard way to add finished extensions without any of this, see how to add extensions on a Chromebook.

What tools help once you're building or testing on a Chromebook?

A handful of narrow, well-scoped extensions cover most day-to-day development and testing tasks without needing Linux or ChromeOS-level developer mode at all.

None of these require ChromeOS developer mode; they run as regular Chrome extensions and work the same whether OS-level developer mode is on or off. Browse more in our developer tools category, or the best Chromebook extensions roundup; picks here follow the same review approach either way.

How do you turn developer mode back off?

Turning it off Powerwashes the device again, the same as turning it on. There's no way to disable developer mode without a full wipe.

1. Turn on the Chromebook; you'll see the OS verification warning screen.
2. Press Space.
3. Confirm by pressing Enter when prompted to re-enable OS verification.
4. The device Powerwashes and reboots into the standard, verified-boot setup screen.

Is developer mode safe, and should most people turn it on?

It's safe for its intended purpose of development and testing, but it does remove a real security layer, so it's not something to leave on without a reason.

If your Chromebook is enrolled in a school or work account, an administrator may block developer mode outright, and attempting it can trigger extra verification steps or a hard lock. Check with your IT admin before trying it on a managed device.