S3 Replication Cost Calculator

S3 replication and cross-region copies are driven by changed data volume. Use this S3 replication cost calculator to estimate monthly replication fees from replicated GB/month and your per-GB assumption.

Inputs

Replicated data (GB / month)
~82.24 GB/day, 7.61 Mbps.
Changed data (GB / day)
Events (per day)
Avg payload (KB)
Est 91.55 GB/day.
Est 2,432 GB/month.
Price ($ / GB)
Replication can be priced as cross-region transfer or as a feature fee.
Scenario presets

Results

Estimated monthly replication cost
$50.00
Replicated volume
2,500 GB

How to get your inputs

  • Inputs: use billing exports, metrics, or logs to get real counts/GB where possible.
  • Units: convert throughput (Mbps) or rates (RPS) into monthly units when needed.
  • Scenarios: build a baseline and a high-usage scenario to avoid under-budgeting.

Result interpretation

  • Replication fees scale with changed data, not total stored GB.
  • Backfills and migrations should be modeled as separate peak months.

Common mistakes

  • Using a single average and ignoring peak/incident scenarios.
  • Double-counting or missing adjacent line items (transfer, logs, retries).

Scenario planning

Scenario Changed GB Direction Notes
Baseline Expected Primary -> replica Steady writes
Peak High Primary -> replica Backfill/migration

Validate after changes

  • Compare your estimate to the first real bill and adjust assumptions.
  • Track the primary driver metric (requests/GB/count) over time.

Next steps

Guides All calculators Guide: S3 replication cost Estimate replication GB/month S3 CRR vs SRR cost Copy storage pricing checklist
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Example scenario

  • 50 GB/day of changed data replicated cross-region (~1,520 GB/month) at your $/GB -> estimate replication fee.
  • Replication volume is often far smaller than total stored GB because it's driven by writes and churn.

Included

  • Replication fee estimate from replicated GB/month and $/GB pricing assumptions.
  • Useful for cross-region replication, backup copy traffic, and sync workloads.

Not included

  • Replica storage costs (model separately).
  • Provider-specific billing rules and request pricing unless you add them separately.

How we calculate

  • Monthly replication fee = replicated GB/month x $/GB.
  • Estimate replicated GB/month from write volume and churn (changed data), not from total stored dataset size.
  • Add destination storage and request fees separately if applicable.

FAQ

How do I estimate replicated GB/month?
Start from write volume (GB/day) or PUTs/day x average object size, then multiply by days per month and replication coverage.
Does replication include destination storage?
No. Replication usually means storing data twice. Add destination storage as a separate line item.

Related tools

Guide: S3 replication cost Estimate replication GB/month S3 CRR vs SRR cost Copy storage pricing checklist S3 cost calculator

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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