How To Find the Serial Number on a Computer

Every computer has a serial number — a unique identifier assigned by the manufacturer before the device ever leaves the factory. Whether you need it for a warranty claim, insurance record, IT asset tracking, or a repair ticket, knowing where to look saves a lot of frustration. The method depends on your operating system, your device type, and sometimes whether the machine will even turn on.

Why Your Serial Number Matters

The serial number is distinct from other identifiers like the model number or product ID. It's specific to your individual unit — no two computers share the same serial number from the same manufacturer. Manufacturers use it to look up your purchase date, warranty status, and service history. It's also what you'll need if a device is stolen and you're filing a police report or insurance claim.

Finding the Serial Number on a Windows PC 🖥️

Method 1: Command Prompt

The fastest way on most Windows machines is through the Command Prompt:

1. Press Windows + R, type cmd, and hit Enter
2. In the command window, type: wmic bios get serialnumber
3. Press Enter — the serial number appears on the next line

This reads directly from the system's BIOS/UEFI firmware, where the manufacturer encodes the serial at the factory. It works on most branded desktops and laptops (Dell, HP, Lenovo, ASUS, etc.).

Method 2: PowerShell

If you prefer PowerShell:

1. Right-click the Start button and select Windows PowerShell
2. Type: Get-WmiObject Win32_BIOS | Select-Object SerialNumber
3. Press Enter

The result is identical to the Command Prompt method — both pull from the same BIOS data.

Method 3: System Information

1. Press Windows + R, type msinfo32, and press Enter
2. Under System Summary, look for System Serial Number in the right panel

A Note on Custom-Built PCs

If you built your own desktop, or the machine was assembled by a small shop, the BIOS serial number field may show as "To be filled by O.E.M." or a string of zeros. In that case, there's no single system-wide serial — you'd track individual component serials (motherboard, GPU, etc.) separately.

Finding the Serial Number on a Mac 💻

From the Apple Menu

1. Click the Apple logo in the top-left corner
2. Select About This Mac
3. The serial number is listed directly in the overview panel (macOS Ventura and later may require clicking More Info, then scrolling to find it under the hardware details)

From System Information

For older macOS versions:

1. Hold Option and click the Apple menu
2. Select System Information
3. Under Hardware Overview, find Serial Number (system)

Using Terminal

If you prefer the command line: system_profiler SPHardwareDataType | grep "Serial Number"

This returns the same serial shown in the GUI.

Finding It on a Chromebook

1. Open Chrome browser and go to chrome://system
2. Search for serial_number in the filter box
3. The value appears inline — no additional tools needed

Alternatively, many Chromebooks display the serial on a sticker on the bottom of the device.

Physical Labels: When Software Isn't an Option

If the computer won't boot, or you simply want a quick reference without logging in, the serial number is usually printed on a physical label:

On some newer MacBooks, Apple also prints the serial number inside the battery compartment, though this requires partial disassembly and isn't practical for quick lookups.

Checking the Original Packaging or Documentation

If the label has worn off or the device has been rehoused, the serial number may still appear on:

• The original retail box (usually a barcode sticker)
• The purchase receipt or invoice
• Your manufacturer account — if you registered the product, brands like Apple, Dell, HP, and Lenovo store the serial in your account's device list

Variables That Affect Which Method Works for You 🔍

Not every approach works in every situation. A few factors determine which path makes the most sense:

• Operating system version — older Windows versions use slightly different command syntax; older macOS versions place serial info in different menu locations
• Whether the device powers on — software methods require a working system; a dead machine means you're relying on physical labels or documentation
• OEM vs. custom build — branded machines reliably encode serials in BIOS; custom builds may not
• Device age — very old hardware may have worn or faded label stickers, and firmware entries may be incomplete
• Device type — laptops, desktops, and all-in-ones each have different physical label placements

For most users on a standard branded laptop or desktop, the Command Prompt method on Windows or the About This Mac panel on macOS returns an accurate result in under a minute. But if the machine is older, heavily modified, or not booting, the approach that actually works for your situation may be a different one entirely.