Side-by-side specifications of the Synology DS215j and DS216, from official datasheets. Differences are highlighted.
| DS215j | DS216 | |
| CPU | Marvell Armada 375 | null |
| Cores / threads | 2 | null |
| RAM (base) | 512MB DDR3 | null |
| RAM (max) | 512MB | null |
| Drive bays | 2 | 2 |
| Expandable to | 0 | 0 |
| M.2 slots | 0 | 0 |
| Network | 1x Gigabit | 1x 1GbE |
| 10GbE | no | no |
| Max raw capacity | 12TB | 16TB |
| Hot-swap | yes | yes |
| Form factor | desktop | desktop |
| Released | 2015 | 2016 |
Choose the DS216 if you want the better overall platform: it has a faster CPU and more RAM headroom than the DS215j, so it will feel snappier and age better. Both are 2-bay units with no expansion to more bays, and neither offers 10GbE or M.2. Pick the DS215j only if it’s significantly cheaper and your use is very light.