Backup Time Calculator
Calculate how long a backup will take given data size and transfer speed.
About This Calculator
Calculate how long a backup will take given data size and transfer speed. Use the calculator above for instant results.
Worked Examples
- 500 × 1024 / 50 = 10,240 sec = 170.7 min = 2.84 hours
- Fits within backup window
Answer: 2.84 hours
- 10,240 × 1024 / 100 = 29 hours! Exceeds backup window
Answer: 29 hours — exceeds window
- 34 minutes — very fast
Answer: ~34 minutes
Who Uses This Calculator?
Plan backup windows.
Capacity plan backup infrastructure.
Size backup systems.
Verify backup fits nightly window.
Common Mistakes to Avoid
❌ Network backup is usually slower
Disk-to-disk over LAN: 50-500 MB/s. Cloud/WAN: 10-100 MB/s. Compression and deduplication can significantly reduce transfer size.
❌ Incremental reduces time
Instead of full backups every night, use incrementals (only changed data). 5-10% change rate reduces nightly backup significantly.
Frequently Asked Questions
Backup speed expectations?
Local disk to disk: 200-500 MB/s. LAN backup: 50-200 MB/s. Cloud backup: 10-100 Mbps (1.25-12.5 MB/s). Tape LTO-9: 400 MB/s native.
Backup window?
The time when systems are quiet enough for backup. Typically overnight (8-10 hours). If backup can't finish in this window, use incremental.
Speed up backups?
Incremental approach. Deduplication. Compression. Parallel streams. Faster network. Direct-attach vs network share.