Snapshot Calculator
Use this tool to figure out which archival snapshots you need to download for a given epoch. It checks the Forest Archive for availability and generates a download script.
For background on how lite and diff snapshots work together, see the Archival Snapshots guide.
Modes
Use state — read historical state (e.g., actor balances via StateGetActor).
Needs the base lite snapshot and diffs up to the target epoch.
Validate / Recompute — re-execute messages and verify state roots
(forest-dev state validate). Validation looks back up to 2000 epochs, but
lite snapshots only contain 900 epochs of state. When the target is close to
the base lite, the calculator adds the previous segment to cover the full
lookback. See the validation caveat.
Minimal snapshots to query state via RPC (e.g., forest-cli state compute).