What to Know Make sure your Chromebook is turned off before you begin.
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Press Esc + Refresh while pressing the Power button. Press Ctrl + D when you see a message that says, Chrome OS is missing or damaged .
+ while pressing the button. Press + when you see a message that says, . Developer mode gives you access to Chrome OS developer shell or Crosh. Press Ctrl+Alt+T to open it in the Chrome browser.
This article explains how to enable developer mode on your Chromebook. Instructions apply to Chromebooks that use a virtualized developer switch. Some Chromebooks, like the Cr-48 and Samsung Series 5, have physical developer mode switches. Chromium maintains a list of Chromebook models where you can find out if your device has a developer switch.
How to Enable Developer Mode on Your Chromebook
To enable developer mode on a Chromebook:
With the Chromebook turned off, boot into recovery mode by pressing Esc+Refresh while pressing the Power button. The Refresh key looks like a circular arrow pointing in a clockwise direction. It's usually the F3 key. Wait for the screen that says Chrome OS is missing or damaged. Please insert USB stick, then press Ctrl+D. Chrome OS isn't missing or damaged. This is the normal screen you get when turning on developer mode. Press Enter if prompted and wait for the device to reboot. Once it restarts, follow the on-screen prompts to set up your Chromebook.
What Is Developer Mode on Chromebooks?
Enabling developer mode is similar to jailbreaking an iPhone or rooting an Android phone. These devices only allow you to install approved apps and provide limited ability to change the system.
When you enable developer mode, you gain a higher degree of control over your device. However, the Chromebook loses all of the security features built into Chrome OS.
Enabling developer mode also powerwashes the Chromebook, which means your login information and any locally-stored data is removed. You can't restore this data, so back up anything you don't want to lose.
What Can You Do With a Chromebook in Developer Mode?
The most important thing that changes when you enable developer mode is you gain access to the Chrome OS developer shell, also known as Crosh. Press Ctrl+Alt+T to open Crosh in the Chrome browser.
The developer shell allows you to perform advanced tasks like pinging an IP address or website, connecting to a Secure Shell (SSH) server, and running other Linux commands. These tasks are possible because Chrome OS is based on Linux.
One useful thing that developer mode enables is the ability to install a Linux desktop environment on your Chromebook. You can retain the Chrome OS interface and switch to a full Linux environment whenever you need to do anything more complicated.
You can access the developer shell without enabling developer mode. Still, developer mode must be turned on to run advanced Linux commands.
Problems With Chromebook Developer Mode
There are a few potential hazards to take into consideration before you enable developer mode:
Google doesn't support it . You might void the warranty when you enable developer mode. This means you could be on your own if you have any problems with your Chromebook in the future.
. You might void the warranty when you enable developer mode. This means you could be on your own if you have any problems with your Chromebook in the future. You lose all your data . Enabling developer mode deletes all the data you stored locally on your Chromebook. If you don't back up everything, it's gone forever.
. Enabling developer mode deletes all the data you stored locally on your Chromebook. If you don't back up everything, it's gone forever. It's easy to lose your data again . When you turn off developer mode, your data gets erased again. You can disable it by pressing the space bar while the Chromebook boots up, so it's easy to wipe the hard drive by accident.
. When you turn off developer mode, your data gets erased again. You can disable it by pressing the space bar while the Chromebook boots up, so it's easy to wipe the hard drive by accident. It takes longer to boot up . Every time you boot up with developer mode on, you have to look at a warning screen.
. Every time you boot up with developer mode on, you have to look at a warning screen. Your Chromebook is less secure. Chromebooks come with many safety features that are disabled when you turn on developer mode.
How to Disable Developer Mode
To disable developer mode, turn off the Chromebook and turn it back on, then wait for the screen that says OS verification is OFF and press the spacebar. Follow the on-screen prompts to set up your Chromebook again.
All locally stored data is removed, so back up your data before disabling developer mode.