Laptop screw sizes explained
Most laptops use only four or five distinct screws, but they are not interchangeable — and the ones near the hinge are usually longer than the rest.
The sizes you will meet
M2 x 3 to M2 x 5 holds boards, SSDs, fans, brackets and speaker mounts.
M2.5 x 5 to M2.5 x 8 is the classic bottom-cover screw on business laptops.
M1.6 x 2 to M1.6 x 4 secures hinges, cameras, small connectors and shields.
M1.2 and M1.4 turn up in the thinnest machines, on trackpad and antenna brackets.
M3 shows up mostly in thicker gaming laptops and drive cages.
Why length matters more than you think
Bottom covers often mix two lengths — long screws near the hinge, short ones at the front lip. Put a long screw in a short hole and you push through the keyboard deck or crack a board.
Lay screws out on a magnetic mat or a piece of tape in the same layout as the laptop. It takes ten seconds and saves a repair.
Replacing a lost screw
Measure a neighbouring screw from the same row, not one from the other side of the machine.
If you cannot measure, start with the shortest plausible length. A slightly short screw holds; a long one destroys.
Check the head shape too. Countersunk screws must sit flush or the cover will bow.
Common questions
What size are most laptop bottom screws?
M2.5 is the most common on business laptops, usually 5 to 8 mm long. Thin consumer machines often use M2 instead.
Are laptop screws the same across brands?
The thread sizes are standard metric, so an M2 x 4 from one brand fits an M2 x 4 hole in another. The head shape and finish may differ.
Can I use a slightly longer screw?
No. In a laptop, 1 mm too long is enough to press on a board or dent the keyboard.
Keep reading
Tools and screws for this job
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Metric screw assortment kit
One box covering the sizes in this guide
Precision driver and bit set
The right bit is what stops rounded heads
Digital caliper
Measure before you buy anything