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Backup Retention Cost Calculator

Estimate backup storage retained and monthly storage cost from retention, change rate, compression, and copies.

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Inputs

GB
GB/day
days

Your values stay on this device.

Results

Estimated Monthly Cost
Retained Storage4.77
Estimated Annual Cost$234.67
Raw Retained Data4,400

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Assumptions

  • Pricing is user-entered because storage, backup, and archive plans vary.
  • The model uses a simple full-plus-change retention estimate, not a vendor-specific deduplication engine.
  • Calculations run locally in your browser and are for planning only.

Sensitivity preview

Full Backup Size -10%: Estimated Monthly Cost $18.67

Full Backup Size Current: Estimated Monthly Cost $19.56

Full Backup Size +10%: Estimated Monthly Cost $20.44

Formula: Retained GB = (full backup GB + daily changed GB * retention days) / compression ratio * copy count. Monthly cost = retained TB * price per TB-month.

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About this Backup Retention Cost Calculator

Backup retention policies can quietly multiply storage use. Full backups, daily change volume, compression, and offsite copies all affect the retained footprint.

Who this calculator is for

  • IT teams sizing backup repositories and archive buckets.
  • MSPs estimating backup storage for clients.
  • Operations teams comparing retention and copy-count policies.

When to use it

  • Estimate retained backup storage for a daily backup policy.
  • Compare 30-day and 90-day retention before buying storage.
  • Model offsite or immutable copy multipliers.

How to use this calculator

  1. Enter the protected full backup size.
  2. Enter average daily changed data and retention days.
  3. Adjust compression, copy count, and price per TB-month.
  4. Review retained storage, monthly cost, and estimated annual cost.

Key assumptions

  • Pricing is user-entered because storage, backup, and archive plans vary.
  • The model uses a simple full-plus-change retention estimate, not a vendor-specific deduplication engine.
  • Calculations run locally in your browser and are for planning only.

Dataset sources

Storage vendor public pricing pages and APIs
Effective date
2026-05-05
Last reviewed
2026-05-05

Storage pricing varies by region, tier, operations, retrieval, minimum duration, egress, support plan, and contract terms.

Public storage-provider list-price references summarized for backup/archive/PACS planning.

Accuracy and testing

Review formula sources, default test cases, assumptions, unit handling, rounding rules, and changelog for this calculator.

View accuracy page

How this calculator works

Retained GB = (Full backup GB + Daily changed GB x Retention days) / Compression ratio x Copy count. Monthly cost = Retained TB x Price per TB-month.
Retained GB = (full backup GB + daily changed GB * retention days) / compression ratio * copy count. Monthly cost = retained TB * price per TB-month.

Inputs explained

Full backup size

The baseline protected data size before compression.

Daily changed data

Average new or changed data retained each day.

Compression ratio

A 2:1 ratio means retained storage is half the uncompressed estimate.

Copy count

Number of retained copies, replicas, immutable copies, or offsite copies billed as storage.

Understanding your results

Use the retained TB and monthly cost as a planning estimate. Real backup platforms may add metadata, synthetic fulls, dedupe behavior, minimum charges, and archive retrieval fees.

Example scenarios

Small server policy

2,000 GB full backup plus 80 GB daily change for 30 days equals 4,400 GB before compression and copy multipliers.

Key Features

  • Instant Calculation
  • Private & Secure
  • Mobile Optimized

Tips & Best Practices

  • Use measured backup repository growth when available.
  • Run a high-change scenario for databases, file shares, and virtual machines with churn.
  • Include immutable or offsite copies when those are billed separately.

Frequently Asked Questions

Does this include deduplication?
Only through the compression ratio you enter. Vendor deduplication varies by workload, block size, retention policy, and backup architecture.
Should archive retrieval charges be included?
No. This calculator estimates retained storage cost. Add retrieval, API, and restore testing costs separately if they are material.
Are backup sizes stored?
No. The calculation runs locally in your browser.