Side-by-side specifications of the Synology DS218 and DS218+, from official datasheets. Differences are highlighted.
| DS218 | DS218+ | |
| CPU | Realtek RTD1296 | Intel Celeron J3355 |
| Cores / threads | 4-core | 2C/2T |
| RAM (base) | 2 GB | 2 GB |
| RAM (max) | 2 GB | 6 GB |
| Drive bays | 2 | 2 |
| Expandable to | — | 0 |
| M.2 slots | — | 0 |
| Network | 1x 1GbE | 1x 1GbE RJ-45 |
| 10GbE | no | no |
| Max raw capacity | 20TB | 20 TB |
| Hot-swap | yes | yes |
| Form factor | desktop | desktop |
| Released | 2018 | 2018 |
Pick the DS218+ if you want more headroom: it has a much faster Intel CPU, supports up to 6GB RAM versus the DS218’s 2GB ceiling, and is the only one of the two with two 1GbE ports for link aggregation. Neither has expansion bays, 10GbE, or M.2 slots; both are 2-bay NAS units. If you’re just doing basic file backup/media storage, the DS218 is fine, but the DS218+ is the better choice for heavier multitasking and apps.