Helm Release History Calculator
Track total Helm release history entries from deploys and rollbacks, and see how many survive pruning under --history-max.
Inputs
Total number of `helm install`/`helm upgrade` operations performed on this release.
Total number of `helm rollback` operations performed (each creates a new revision).
Maximum revisions retained; 0 means unlimited (no pruning).
Retained History Entries
10revisions
Total History Entries Created
21revisions
Pruned Entries
11revisions
Step by step
History entries = deploys + rollbacks
18 + 3
= 21 entries
Retained after pruning
min(21, 10)
= 10 entries
Pruned entries
21 − 10
= 11 entries (52.4%)
How it works
Both deploys (installs/upgrades) and rollbacks create a new revision in a Helm release's history, so the total number of history entries ever created is the sum of the two. Helm continuously prunes the oldest entries once the count exceeds `--history-max`, so the number actually retained and available for future rollback is capped at that limit — meaning very active releases can lose the ability to roll back to early revisions long before the release itself is decommissioned.
Formula
retainedEntries = min(deploys + rollbacks, maxHistory)
- D
- Number of deploy operations (installs + upgrades)
- B
- Number of rollback operations
- H
- Max history setting (0 = unlimited)
- R
- Retained history entries
Frequently Asked Questions
Does a rollback count as a deploy for history purposes?
No — Helm tracks rollbacks as their own revision type distinct from install/upgrade, but both consume a slot in the same bounded history list subject to `--history-max` pruning.
Can I recover a pruned revision?
Not from Helm's own storage — once pruned, the Secret/ConfigMap backing that revision is deleted; recovery would require an external backup of release manifests (e.g. keeping rendered YAML in Git) taken before pruning occurred.
Should history-max be higher for releases that roll back often?
Yes — if a release frequently needs to roll back several versions, a higher `--history-max` keeps more rollback targets available; balance this against the added Secret storage each retained revision costs.