Computer & IT
Email Archive Storage Calculator
Forecast retained archive capacity and run-rate cost from daily raw growth, retention, compression, copies, monthly growth, and access charges.
Current retained raw data-
Current stored data after compression and replicas-
Daily raw volume at forecast end-
Forecast retained raw data-
Forecast stored data after compression and replicas-
Current storage cost per month-
Forecast storage cost per month-
Forecast storage, access, and egress cost-
Annualized forecast run rate-
Stored-capacity growth through horizon-
Decision view
Message stream and retained archive shelves
Message stream and retained archive shelvesMessages and attachments enter archive shelves where retention, compression, copies, and forecast growth remain separate.
Email Archive Storage monthly costForecast month is horizontal and modeled storage, access, and egress cost is vertical.
Exact scenario comparisonRetention period (days) changes while all other entered assumptions remain constant.
| Retention period (days) | Current retained raw data | Current stored data after compression and replicas | Daily raw volume at forecast end | Forecast retained raw data | Forecast stored data after compression and replicas | Current storage cost per month | Forecast storage cost per month | Forecast storage, access, and egress cost | Annualized forecast run rate | Stored-capacity growth through horizon |
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Period-by-period detail
email archive monthly capacity and cost forecast
How to use Email Archive Storage Calculator
- Measure journal or archive ingest including attachments.
- Set the applicable retention window and stored copies.
- Review forecast capacity with search, legal hold, and export needs.
Calculator guide
Understanding Email Archive Storage Calculator
Email archives accumulate messages, attachments, indexes, and retained copies, so mailbox size alone can understate the storage estate.
Calculation method
How the calculation works
Translate daily email archive creation into retained raw volume, apply compression and replica count, project monthly growth, and reconcile current and forecast storage capacity and run-rate cost. Daily archived GB times retention days establishes retained raw mail; compression and copies produce the stored footprint.
Archive flow
File incoming messages into retained archive shelves
The visual separates daily messages, attachment volume, retention shelves, copies, and forecast storage.
Worked situations
Practical examples
- Large attachments can dominate daily archive growth.
- Legal hold may prevent deletion after the normal policy expires.
- Search indexes may reduce the effective compression benefit.
Better inputs
Useful tips
- Separate active mailboxes from immutable archive storage.
- Track held data independently from ordinary retention.
- Include export and e-discovery charges where material.
Before relying on the result
Limitations and common mistakes
- Legal holds, index overhead, deduplication, and per-message charges are simplified.
- One retention rule and blended storage price are modeled.
- The calculator does not define records policy.
Reference
Key terms
- Archive ingest
- New messages and attachments added to archive each day.
- Legal hold
- Preservation rule that can override ordinary deletion.
- Journal copy
- Captured message copy stored for compliance or recordkeeping.
Important note
Calculated from the entered technical values using the displayed model. Validate topology, workloads, capacity, security, redundancy, and observed performance before implementation.
Frequently asked questions
Should active mailbox storage be included?
Only if it is part of the same billed archive estate.
How should legal hold be modeled?
Use a longer effective retention or create a separate held-data scenario.
Does the result include e-discovery?
Only if an estimated monthly amount is included in access and egress cost.