The hiberfil.sys File in Windows: What It Is and Why It’s Important

While navigating your Windows system, you might come across a large file named hiberfil.sys in the root of your system drive (usually C:\). This file often takes up a considerable amount of space on your hard drive, leading many to wonder what it is, if it’s safe to delete, and how it affects your system’s performance. Let’s dive in to clarify its purpose and impact.

What Is the hiberfil.sys File?

The hiberfil.sys file is created by Windows to enable the hibernation feature. Hibernation is a mode that saves the contents of your computer’s RAM (active memory) to the hard drive, allowing you to turn off the computer completely while preserving your open applications, files, and settings. When you power up again, the system quickly restores your previous session from this file as if it hadn’t been shut down.

How Does Hibernation Work?

Unlike sleep mode, which keeps the computer in a low-power state to maintain the contents of RAM, hibernation saves the data to the hard drive and powers off entirely. This mode is especially useful for laptops, as it conserves battery life while allowing users to resume work seamlessly.

Can You Delete the hiberfil.sys File?

Since hiberfil.sys is exclusively used for hibernation, it can be deleted if you disable hibernation. Keep in mind that disabling hibernation means you’ll lose this feature, although regular sleep mode will still be available. However, you’ll no longer be able to completely power off your computer while preserving the session in memory.

How to Disable Hibernation and Remove hiberfil.sys

To turn off hibernation and remove the file, follow these steps:

Open Command Prompt as an administrator (press Win + X and select Command Prompt (Admin)).
In the command line, type powercfg -h off and press Enter.
After this command is executed, hibernation will be disabled, and the hiberfil.sys file will be automatically deleted from your drive.

Can You Adjust the Size of hiberfil.sys?

If you want to keep hibernation enabled but reduce the size of hiberfil.sys, you can try adjusting it with the powercfg command. In the Command Prompt, type powercfg /h /type reduced to attempt to reduce the file size. However, this option is only available in certain Windows versions and may not significantly change the file size.

Should You Disable Hibernation?

Deciding whether to disable hibernation depends on your needs. If you’re using a desktop computer and don’t require the session-saving feature, disabling it can free up several gigabytes on your system drive. However, for laptops where battery conservation is crucial, hibernation is often worth keeping.