Backup Storage Calculator – Total Backup Capacity
Calculate total storage needed for backups with retention and change rate.
About This Calculator
Calculate total storage needed for backups with retention and change rate. Use the calculator above for instant results.
Worked Examples
- Full: 500 GB | Incremental: 750 GB | Total: 1,250 GB
- With 60% compression: ~500 GB
Answer: ~1,250 GB / ~500 GB compressed
- Full: 1,000 GB | Incremental: 9,000 GB | Total: 10 TB
Answer: ~10 TB before compression
- Total: 120 GB | Compressed: ~48 GB
Answer: ~120 GB / ~48 GB compressed
Who Uses This Calculator?
Plan backup storage capacity.
Backup infrastructure sizing.
Capacity planning for backup systems.
Backup strategy and sizing.
Common Mistakes to Avoid
❌ 3-2-1 backup rule
3 copies, 2 different media, 1 offsite. This calculator gives on-premise storage. Also size your offsite/cloud backup separately.
❌ Change rate varies hugely
Databases can change 100%/day. Static websites change 0.1%/day. Know your actual change rate before sizing.
Frequently Asked Questions
What is change rate?
Percentage of data that changes each day. High for databases. Low for archives. Average for business files: 5-10%.
Full vs incremental vs differential?
Full: entire dataset every time. Incremental: only changes since last backup. Differential: changes since last full.
Cloud backup cost?
AWS S3: ~$0.023/GB/month. Glacier: $0.004. Backblaze B2: $0.006. Onsite tape or disk often cheaper for large datasets.