The fastest way to reach BIOS depends on your computer's manufacturer

To enter BIOS, restart your computer and press a specific key repeatedly as it boots up — before Windows or your operating system loads. The key you press depends on who made your machine: Dell computers usually respond to F2, HP and Lenovo machines to F10, Asus to Delete, and Apple computers to Command-R (though Apple calls it Firmware, not BIOS). You have only a few seconds after power-on to catch the window, so you may need to restart a few times to time it right.

If you miss the window on your first try, let the computer finish booting into Windows, then shut it down completely and try again. Holding the key down rather than tapping it works better on some machines — if tapping doesn't work, try holding it from the moment you press the power button.

Key Takeaways

  • The key to press depends on your computer brand: F2 for Dell, F10 for HP and Lenovo, Delete for Asus, and Command-R for Mac.
  • You must press the key during the startup sequence, before your operating system loads — usually within the first few seconds after power-on.
  • If you miss the window, shut down completely and restart; holding the key down works better than tapping it on many machines.
  • Once inside BIOS, use arrow keys to navigate and Enter to select; look for an Exit or Save option to leave without making changes.

Finding your computer's BIOS key if you don't know the brand

If you're not sure who made your computer, check the startup screen itself. Most machines display the correct key on the boot screen — you'll see text like "Press F2 to enter Setup" or "Press Delete for BIOS" in the bottom corner. Read this message carefully before it disappears, because it tells you exactly what to do.

If the message goes by too fast, restart and watch for it again. You can also check your computer's manual or the manufacturer's website by searching "[Your Brand] BIOS key" — for example, "Acer BIOS key" or "MSI BIOS key." The answer is usually on the first result.

Timing your keypress during startup

The BIOS window opens for only a few seconds after you press the power button. Start pressing your key when ready after the computer powers on, and keep pressing it every half-second or so until the BIOS screen appears. If the computer boots all the way into Windows, you waited too long — shut down and try again.

Some computers are faster than others. Newer machines with solid-state drives boot so quickly that you may have only two or three seconds to react. If you find yourself repeatedly missing the window, try holding the key down continuously from the moment you press power, rather than tapping it. This removes the timing problem entirely.

What you'll see once you're inside BIOS

BIOS looks different depending on your manufacturer, but the layout is usually similar: a menu on the left or top, settings in the middle, and help text on the right. The screen is text-only and uses a dark background. You navigate using arrow keys on your keyboard — not your mouse, which usually doesn't work in BIOS.

Common sections you'll see include Boot Order (which device starts first), System Information (your hardware details), Security (passwords and startup settings), and Power Management (sleep and shutdown behavior). Don't change anything unless you know what you're doing — BIOS controls how your computer starts up, and wrong changes can prevent it from booting.

Leaving BIOS without making changes

If you entered BIOS by accident or just wanted to look around, you can leave without saving. Look for an Exit menu, usually at the bottom of the screen or in a separate menu. Select "Exit Without Saving" or "Discard Changes" — the exact wording varies by manufacturer. Your computer will restart and boot normally into Windows.

If you made changes and want to keep them, look for "Save and Exit" instead. BIOS will save your changes and restart. If you're unsure whether you changed anything, use "Exit Without Saving" — it's the safer choice.

Common reasons people enter BIOS

Most people enter BIOS to change the boot order — for example, to boot from a USB drive instead of the hard drive, which is necessary when installing Windows or running a recovery tool. Others enter to check hardware information, disable a device, or change power settings. Some enter by accident and just want to leave.

If you're trying to boot from a USB drive, you may have a faster option: many computers let you press a different key during startup to choose a boot device without entering BIOS. This key is often F12, Esc, or F9, and it's usually shown on the startup screen. This method is faster than changing the boot order inside BIOS itself.

Troubleshooting if you can't reach BIOS

If you press the correct key but nothing happens, your computer may be booting too fast, or you may be pressing the wrong key. Try restarting and watching the startup screen more carefully for the correct key to press. If the screen goes by too fast to read, try pressing Pause on your keyboard during startup — this freezes the boot screen so you can read it.

If you have a password set on BIOS, you'll be asked to enter it before you can access the settings. If you don't remember the password, you may need to reset it — this usually requires opening the computer case and removing a small battery on the motherboard for a few minutes, or pressing a jumper. Check your computer's manual for the exact procedure, as it varies by model.

Frequently Asked Questions

What's the difference between BIOS and UEFI?

UEFI is the newer version of BIOS and works the same way from the user's perspective — you still restart and press a key to enter it. The main difference is that UEFI supports larger hard drives and has a slightly more modern interface, but you navigate it the same way with arrow keys and Enter. Most computers made after 2010 use UEFI instead of older BIOS.

Can I damage my computer by entering BIOS?

Entering BIOS and looking around causes no damage. Changing settings can cause problems if you don't know what you're doing — for example, disabling a device or changing boot order incorrectly can prevent your computer from starting. If you make a change and something breaks, restart and enter BIOS again to undo it, or use "Exit Without Saving" if you haven't saved yet.

Why does my computer boot so fast I can't catch the BIOS key?

Modern computers with solid-state drives boot in just a few seconds. Try holding down the BIOS key continuously from the moment you press the power button, rather than tapping it. If that doesn't work, restart and press Pause on your keyboard during the startup screen to freeze it, so you can read which key to press and have more time to react.

Is BIOS the same as the Windows startup menu?

No. BIOS is the system that runs before Windows loads. The Windows startup menu appears after Windows has already started to load. If you want to change which device your computer boots from, you need BIOS, not the Windows startup menu. The BIOS key is pressed when ready after power-on; the Windows startup menu key is pressed after you see the Windows logo.