OneDrive storage tool
OneDrive Migration Size Estimator
Estimate transferable OneDrive data after duplicate cleanup, exclusions and growth buffer.
Buffered migration size
1.1 TB
- Current transferable data
- 1,025 GB
- Data avoided
- 175 GB
Estimated transfer size
Avoided duplicate data
Buffered migration volume
How it works
A useful answer in three clear steps.
- 1
Enter source size
Complete this check before moving to the next decision.
- 2
Add reviewed duplicates and exclusions
Complete this check before moving to the next decision.
- 3
Apply a growth buffer before scheduling
Verify the final result against your current cloud drive or organizational policy.
Frequently asked questions
Before you use this tool
Is the Migration Size Estimator free to use?
Yes. You can use this tool in the browser without creating an account or installing software.
How accurate is the Migration Size Estimator?
The arithmetic uses the values you provide. Its usefulness depends on whether those inputs represent the real drive, team or transfer conditions, so treat the result as a planning estimate.
Can this tool delete or change my cloud-drive files?
No. This page does not connect to your cloud account and cannot rename, move or delete files. It produces an estimate, analysis or checklist for you to review.
What should I do after using the Migration Size Estimator?
Apply a growth buffer before scheduling. Discovery, permissions, versions and unsupported files can affect migration scope independently of bytes.
Keep exploring
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Storage Growth Forecast
Project future OneDrive usage from current storage and average monthly growth.
Storage Full-Date Calculator
Estimate when a OneDrive quota will be full at the current monthly growth rate.
Ready to measure duplicate storage with real data?
Choose OneDrive or Dropbox for a read-only scan, then review exact fingerprint matches before any cleanup decision.