Backup Storage Retention Calculator
Model full, incremental and differential backup events with explicit retention and restore dependency rules.
A QUICK WALKTHROUGH
How to use this tool
- Name scenarios and enter the period or backup schedule.
- Choose the calculation and eligibility or dependency model, then enter quantities with units.
- Calculate and inspect every trace before copying or downloading the fixed report.
Model
Full bytes = initial bytes + daily growth × creation day. Stored bytes = logical bytes × copies × user multiplier. Incremental restore points require their full and every later increment; differential restore points require their full and that differential. Independent mode retains objects by age without claiming a usable restore chain. Retention preserves every in-window restore point and any older required dependencies. The report includes each event and every expiry boundary, with inclusive and immediately-after states. Storage peaks are sampled at all event and expiry transitions; fees and recovery success are not predicted.
Backup model
Boundary: event at day 0, frequency steps ≤ horizon; retained timestamps ≥ observation day − retention. Full cycle is a count of backup events. Increment/difference = (growth + changed existing volume) × elapsed days since prior/full backup. Multiplier is a user assumption, not predicted compression or deduplication.
Results
Exact fractions; display decimals are rounded. All processing stays in this browser. Maximum 10 scenarios and 200 events/interval rows per scenario; larger input is rejected. Decimal input: up to 300 characters; signs and a decimal point only, no scientific notation. (+) means immediately after the exact expiry boundary, with no added time. Scenario names: 1–200 characters.
GOOD TO KNOW
Common questions
Model?
Boundary: event at day 0, frequency steps ≤ horizon; retained timestamps ≥ observation day − retention. Full cycle is a count of backup events. Increment/difference = (growth + changed existing volume) × elapsed days since prior/full backup. Multiplier is a user assumption, not predicted compression or deduplication.
Invalid or missing value; check units, ranges and row format.?
Maximum 10 scenarios and 200 events/interval rows per scenario; larger input is rejected. Decimal input: up to 300 characters; signs and a decimal point only, no scientific notation. (+) means immediately after the exact expiry boundary, with no added time. Scenario names: 1–200 characters.