A type of computer memory integrated circuit, a SO-DIMM (from Small Outline DIMM) is a smaller alternative to a DIMM. As a result of being roughly half the size of regular DIMMs, SO-DIMMs are mainly utilised in laptops and small footprint PCs.

SO-DIMMs have 72 pins (supporting 32-bit data transfer) or 144 pins or 200 pins (both supporting 64-bit data transfer). This compares to regular DIMMs that have 168 pins and support 64-bit data transfer.