A Simple Guide to M.2 SSD Form Factors, Dimensions, and Compatibility

If you've ever shopped for an SSD, you've probably seen codes like 2280 or 2242 and wondered what they mean. These numbers aren't random — they describe the physical size of the drive. Getting this right matters, because the wrong M.2 size simply won't fit your device.

What is M.2?

M.2 is a compact form factor for SSDs used in laptops, desktops, and mini-PCs. It replaced the older mSATA standard and has become the default choice for modern storage due to its small footprint and support for fast interfaces like NVMe (PCIe) and SATA.

Unlike a traditional 2.5-inch drive, M.2 SSDs plug directly into a slot on the motherboard — no cables required. That makes installation cleaner and faster.

How M.2 Size Codes Work

M.2 sizes are described by a four or five digit number — the first two digits are the width in millimeters, and the remaining digits are the length in millimeters. So a 2280 drive is 22mm wide and 80mm long. Simple once you know the pattern.

The Most Common M.2 Sizes

• 2242 — 22mm × 42mm. Compact drives used in smaller laptops, tablets, and mini-PCs where space is limited. Less common but still found in ultrabooks and industrial devices.
• 2260 — 22mm × 60mm. A middle-ground size, occasionally found in older laptops and some embedded systems. Rarely seen in modern consumer hardware.
• 2280 — 22mm × 80mm. The most common size by far. Supported by virtually every modern motherboard and laptop M.2 slot. If you're buying an SSD and unsure which size to get, this is almost always the right answer.
• 22110 — 22mm × 110mm. The longest standard M.2 size, sometimes called "M.2 ruler" format. Found in enterprise-grade storage and high-end workstation motherboards. Rare in consumer systems.

Which Size Do You Need?

For most users building or upgrading a desktop PC or laptop — 2280 is the answer. Check your motherboard's manual or your laptop's spec sheet to confirm, but 2280 support is nearly universal in hardware made after 2016.

If you're upgrading a compact device like an Intel NUC, Surface Pro, or older ultrabook, double-check before buying — these sometimes require a 2242 drive. Installing the wrong size means the drive won't reach the mounting screw and won't be secured properly.

NVMe vs. SATA: The Other Variable

Size is only half the equation. M.2 slots support two different interfaces — NVMe (PCIe) and SATA — and not all slots support both. NVMe drives are significantly faster (up to 7,000+ MB/s on PCIe 4.0 vs. ~550 MB/s for SATA), but an NVMe drive won't work in a SATA-only slot. Always check your motherboard or laptop specs before buying.

Quick Reference

• 2242 — compact devices, ultrabooks, mini-PCs
• 2260 — older laptops, rare in modern hardware
• 2280 — standard size, works in almost everything
• 22110 — enterprise and high-end workstations only

When in doubt — check your device's manual, confirm the slot interface (NVMe or SATA), and go with 2280. It's the safe choice for the vast majority of builds and upgrades.