Thin laptops mean soldered RAM.

Basically, if the laptop is under 18mm thick, you’re almost certainly stuck with whatever RAM came installed.

The reason is simple: physical space. SODIMM slots need height—about 4-5mm for the slot and module together. In an ultrabook, every millimeter is already spoken for by the battery, cooling, and screen hinge. Soldering the RAM chips directly to the board saves that space and lets manufacturers make the chassis thinner.

Gaming laptops, which are usually 20mm+ thick, still have room for traditional slots. But even there it’s not guaranteed—some manufacturers solder RAM to save cost even when they have the space. And many gaming laptops now use both: two soldered chips and one slot, or only soldered.

If you care about upgrading later, check the spec sheet for “SODIMM” or “user-replaceable” before you buy. Thickness is a