ZFS storage planning tools

Start with a capacity scenario, then read the guides for the choices behind it. The calculator runs in your browser and requires no account. Keep its assumptions with your plan so changes in disk count, parity or expected compression are easy to compare.

ZFS and RAIDZ capacity calculator

Compare RAIDZ1, RAIDZ2 and RAIDZ3 for a proposed vdev. Enter disk count and size to see capacity after parity, an 80% planning budget, and logical storage at a compression ratio you supply. The explanation covers TB versus TiB, allocation overhead, snapshots and the limits of the estimate.

Review the assumptions

Use the parity comparison to consider recovery and expansion. Budget memory separately with the ZFS RAM requirements guide; for an existing host, follow the ARC size guide to inspect usage before changing a limit.

If a running pool needs attention, begin with the degraded-pool guide. For other questions, browse all topics.