Database Restore Time Calculator
Estimate restore time from backup size, throughput and replay of incrementals.
About Database Restore Time Calculator
Restore time is what a recovery objective actually measures, and long incremental chains often dominate it. Taking full backups more often shortens the chain at the cost of storage. Backup strategies are frequently designed around backup windows and never tested against restore time, which is the number that matters during an incident.
Formula
Database Restore Time
Restore time = backup size ÷ throughput + incrementals × replay time per increment
- recovery time objective
- Maximum acceptable outage duration
- replay
- Applying incremental changes after the full restore
Worked example
With the default values below, Database Restore Time Calculator returns Estimated Restore Time of 0.885. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Compressed backup sizeminimum 0 GB
- 120 GB
- Restore throughputminimum 0.01 MB/s
- 400 MB/s
- Incremental backups to replayminimum 0
- 12
- Minutes to replay each incrementalminimum 0 min
- 4 min
- Recovery time objectiveminimum 0.01 hours
- 4 hours
Results
- Estimated Restore Time
- 0.885 hours
- Full Backup Restore Time
- 0.085 hours
- Incremental Replay Time
- 0.800 hours
- Share of the Recovery Objective Used
- 22.13%
- Verdict
- Restore fits comfortably within the recovery objective
Step by step
- 1Values used
- 2Database Restore Time
- 3Estimated Restore Time= 0.885 hours
- 4Full Backup Restore Time= 0.085 hours
- 5Incremental Replay Time= 0.800 hours
- 6Share of the Recovery Objective Used= 22.13
- 7Verdict= Restore fits comfortably within the recovery objective
Assumptions and limits
- The result is derived only from the 5 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Database Restore Time calculated?
Restore time = backup size ÷ throughput + incrementals × replay time per increment Restore time is what a recovery objective actually measures, and long incremental chains often dominate it. Taking full backups more often shortens the chain at the cost of storage.
Why does Database Restore Time matter?
Backup strategies are frequently designed around backup windows and never tested against restore time, which is the number that matters during an incident.
What values do I need to enter?
This calculator takes 5 inputs: Compressed backup size, Restore throughput, Incremental backups to replay, Minutes to replay each incremental, Recovery time objective. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.