SizeToolsHub.com
Verified International Size & Measurement Reference Platform
File Size Converter & Multi-Unit Calculator Reference Table
Data Storage Guide
Decimal (SI) vs Binary (IEC) Storage Reference.
Why data storage calculations differ between disk manufacturers and operating systems.
Prefix Multipliers: Decimal (1000) vs Binary (1024)
| Scale | Decimal (SI / Base 10) | Decimal Bytes | Binary (IEC / Base 2) | Binary Bytes | Capacity Difference |
|---|---|---|---|---|---|
| Kilo / Kibi | 1 KB = 1,000 B | 1,000 | 1 KiB = 1,024 B | 1,024 | +2.4% |
| Mega / Mebi | 1 MB = 1,000,000 B | 1,000,000 | 1 MiB = 1,048,576 B | 1,048,576 | +4.86% |
| Giga / Gibi | 1 GB = 1,000,000,000 B | 1,000,000,000 | 1 GiB = 1,073,741,824 B | 1,073,741,824 | +7.37% |
| Tera / Tebi | 1 TB = 10¹² B | 1,000,000,000,000 | 1 TiB = 2⁴⁰ B | 1,099,511,627,776 | +9.95% |
| Peta / Pebi | 1 PB = 10¹⁵ B | 1,000,000,000,000,000 | 1 PiB = 2⁵⁰ B | 1,125,899,906,842,624 | +12.59% |
Real-World Drive Usable Capacity in Windows
| Advertised Drive Size | Manufacturer Bytes | Reported in Windows (GiB) | Discrepancy Cause |
|---|---|---|---|
| 256 GB SSD | 256,000,000,000 | 238.4 GiB | 17.6 GB apparent loss |
| 512 GB SSD | 512,000,000,000 | 476.8 GiB | 35.2 GB apparent loss |
| 1 TB Drive | 1,000,000,000,000 | 931.3 GiB | 68.7 GB apparent loss |
| 2 TB Drive | 2,000,000,000,000 | 1,862.6 GiB | 137.4 GB apparent loss |
| 4 TB Drive | 4,000,000,000,000 | 3,725.3 GiB | 274.7 GB apparent loss |
| 8 TB NAS | 8,000,000,000,000 | 7,450.6 GiB | 549.4 GB apparent loss |
Download Time Reference Matrix
| File Size | 50 Mbps (DSL) | 100 Mbps (Cable) | 300 Mbps (Fiber) | 1,000 Mbps (Gigabit) |
|---|---|---|---|---|
| 1 GB (Movie clip) | 2m 44s | 1m 22s | 27s | 8s |
| 5 GB (HD Movie) | 13m 40s | 6m 50s | 2m 17s | 41s |
| 25 GB (4K Video) | 1h 08m | 34m 08s | 11m 23s | 3m 25s |
| 50 GB (Modern Game) | 2h 16m | 1h 08m | 22m 45s | 6m 50s |
| 100 GB (AAA Title) | 4h 33m | 2h 16m | 45m 31s | 13m 39s |