Database Storage Growth Cost Calculator

If your database grows steadily, average GB over a month is often a better cost estimate than the end-of-month number. Compare baseline vs peak growth rates for planning.

Inputs

Starting size (GB)
~0.49 TB.
Growth (GB / day)
~152 GB/month growth.
Horizon (months)
Storage price ($ / GB-month)
~$122.88 per TB-month.
Scenario presets

Results

Ending size (est.)
1,412 GB
Average size (est.)
956 GB
Estimated monthly cost (average)
$114.72

How to get your inputs

  • Compute: instance-hours (or average serverless capacity) and a peak scenario.
  • Storage: average GB-month plus growth over time.
  • Backups: retention and churn (daily changed data x retention days) as a separate line item.

Result interpretation

  • Average GB is a better budget proxy than end-of-month GB.
  • Daily growth is the key driver; small increases compound over months.

Common mistakes

  • Ignoring backup storage and long-term retention growth.
  • Modeling only today's size and missing 3-12 month growth.

Scenario planning

Scenario Starting GB Growth GB/day Horizon
Baseline Current Expected 6-12 months
Peak Same High 6-12 months

Validate after changes

  • Compare forecast vs actual storage/backup GB-month after a few weeks.
  • Re-check during batch jobs or backfills (churn spikes).

Next steps

Guides All calculators Object storage cost Storage replication
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Example scenario

  • Starting 500 GB and growing 5 GB/day over 6 months -> estimate ending size and average monthly cost.
  • Peak 220% scenario helps budget for launch growth.

Included

  • Ending size estimate using a linear growth assumption.
  • Baseline vs peak scenario table for growth rates.
  • Average size estimate and implied average monthly storage cost.

Not included

  • Non-linear growth, compaction, and retention policies that change growth rate.
  • Replica/index/storage-class multipliers unless you model them in effective GB.

How we calculate

  • Ending GB ~ starting GB + (growth GB/day x days).
  • Average GB ~ (starting + ending) / 2 (linear growth assumption).
  • Estimated monthly cost ~ average GB x storage price per GB-month.

FAQ

Is growth really linear?
Not always. Use this as a planning approximation, and update with real metrics over time.
Should I include indexes and replicas?
Yes, if your provider bills them separately. You can increase the effective storage GB or model components separately.

Related tools

Object storage cost Storage replication

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Disclaimer

Educational use only. Not legal, financial, or professional advice. Results are estimates based on the inputs and assumptions shown on this page. Verify pricing and limits with your providers and documentation.

Last updated: 2026-01-29