The different M.2 SSD form factors

Generally, M.2 SSDs are 22 millimeters wide and 60 mm or 80 mm long; although, card lengths can vary. The card size is identified by a four- or five-digit number. The first two digits are the width and the remaining numbers are the length. For example, a 2260 card is 22 mm wide and 60 mm long. Longer M.2 drives usually hold more NAND chips for extra capacity.

Other sizes include:

• 2280 — 22 mm x 80 mm
• 2230 — 22 mm x 30 mm
• 2242 — 22 mm x 42 mm
• 2260 — 22 mm x 60 mm
• 22110 — 22 mm x 110 mm

The 22 mm width is the standard for desktops and laptops. An 80 mm or 110 mm length card can hold eight NAND chips for 2 terabytes (TB) of capacity.

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