Compare two archive tiers over a full retention period including per-object overhead and restore charges.
Over a multi-year retention period the storage rate is multiplied by 84 or more months, so a 3.6x difference in per-GB rate becomes the dominant term and the deeper tier almost always wins on paper. What claws the gap back is restore behaviour: the deeper tier charges more per GB retrieved and takes hours rather than minutes, so a compliance archive that is read often is not the same decision as one that is never read. Both rate pairs are user-supplied list prices to confirm on the AWS S3 pricing page for your region. Retention periods are usually fixed by policy rather than by engineering, so the only real lever is tier choice, and that choice turns entirely on how often the archive is actually restored.
Archive Cost
tier total = (data GB + objects x 40 KB) x rate x months held + restored GB x retrieval rate, with restored GB = billable GB x restore share x years.
tier total = (data GB + objects x 40 KB) x rate x months held + restored GB x retrieval rate, with restored GB = billable GB x restore share x years. Over a multi-year retention period the storage rate is multiplied by 84 or more months, so a 3.6x difference in per-GB rate becomes the dominant term and the deeper tier almost always wins on paper. What claws the gap back is restore behaviour: the deeper tier charges more per GB retrieved and takes hours rather than minutes, so a compliance archive that is read often is not the same decision as one that is never read. Both rate pairs are user-supplied list prices to confirm on the AWS S3 pricing page for your region.
Retention periods are usually fixed by policy rather than by engineering, so the only real lever is tier choice, and that choice turns entirely on how often the archive is actually restored.
This calculator takes 8 inputs: Data to archive, Objects to archive, Retention period, Deeper tier storage price, Faster tier storage price, Share of the archive restored each year, Deeper tier retrieval price, Faster tier retrieval price. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
Often yes. Deep Archive standard retrieval takes up to 12 hours and bulk up to 48, so an archive with a recovery time objective measured in minutes cannot use it regardless of how much cheaper the storage is.