The short answer
Start with the size of the files you intend to keep, add expected growth over a chosen period and apply a buffer. Count independent backups separately. “1 TB” is not a workload: your own file sizes provide a better starting point.
Measure before forecasting
Use a local file inventory to total a representative selection. Separate working documents, photographs and videos because their sizes can differ greatly. The inventory tool reads selected names and byte lengths; it does not scan your whole device or upload contents.
Use a transparent example
Suppose 1,000 files average 5 MB. Their initial total is 5 GB in decimal units. Adding 2 GB per month for 12 months gives 29 GB. A 20% buffer makes the planning allowance 34.8 GB. These inputs illustrate arithmetic, not typical user behavior.
Revisit the forecast
Compare the estimate with actual usage after a normal project cycle. Add separate requirements for retained backup copies, camera originals or exported deliverables. Do not assume that deleting a working file immediately removes every retained copy in a provider’s system.
Checklist
- 1Total the intended files.
- 2Choose a planning period.
- 3Estimate growth from your own history.
- 4Apply a buffer and plan backups separately.
Good questions. Clear answers.
How many files fit in 100 GB?
At an assumed average of 5 MB, 100 decimal GB holds about 20,000 files before additional overhead or retained versions.
Does the calculator recommend a subscription?
No. It estimates capacity from your inputs; compare the result with current provider plans separately.
Related free tools
Estimate the space for your files, monthly growth and a capacity buffer.
Local file inventory and size analyzerReview selected local files by extension, total bytes and largest files, then export an inventory.
Photo storage calculatorPlan storage for a photo collection using image count, average file size and extra space.