File Size Converter
Convert file sizes between different units of measurement.
Understanding File Size Units
File sizes are measured in different units, and understanding the relationship between them is crucial for managing storage, bandwidth, and data transfer.
Decimal vs Binary Units
There are two systems for measuring file sizes:
Decimal Units (SI Standard)
Based on powers of 1000, these units follow the International System of Units (SI):
- Byte (B): 1 byte = 8 bits
- Kilobyte (KB): 1,000 bytes
- Megabyte (MB): 1,000 KB = 1,000,000 bytes
- Gigabyte (GB): 1,000 MB = 1,000,000,000 bytes
- Terabyte (TB): 1,000 GB = 1,000,000,000,000 bytes
- Petabyte (PB): 1,000 TB
Common Use: Hard drive manufacturers, network speeds, storage device marketing
Binary Units (IEC Standard)
Based on powers of 1024, these units are defined by the International Electrotechnical Commission (IEC):
- Kibibyte (KiB): 1,024 bytes
- Mebibyte (MiB): 1,024 KiB = 1,048,576 bytes
- Gibibyte (GiB): 1,024 MiB = 1,073,741,824 bytes
- Tebibyte (TiB): 1,024 GiB = 1,099,511,627,776 bytes
Common Use: Operating systems, memory (RAM), actual file system calculations
Why the Difference Matters
This is why a 1 TB hard drive shows as only 931 GB in your operating system. The manufacturer uses decimal (1 TB = 1,000,000,000,000 bytes), but your OS uses binary (1 TiB = 1,099,511,627,776 bytes).
Example: 1 TB Hard Drive
Manufacturer (Decimal): 1,000,000,000,000 bytes = 1 TB
Operating System (Binary): 1,000,000,000,000 bytes = 931.32 GiB
Common File Sizes
| File Type | Typical Size |
|---|---|
| Text Document | 10-100 KB |
| 20-200 KB | |
| Photo (JPEG) | 2-12 MB |
| Photo (RAW) | 20-50 MB |
| MP3 Song (3-4 min) | 3-5 MB |
| HD Movie (1080p) | 4-8 GB |
| 4K Movie | 20-50 GB |
| AAA Video Game | 50-150 GB |
Quick Conversion Reference
| Decimal | Binary | Bytes | Difference |
|---|---|---|---|
| 1 KB | 1 KiB | 1,000 vs 1,024 | 2.4% |
| 1 MB | 1 MiB | 1,000,000 vs 1,048,576 | 4.9% |
| 1 GB | 1 GiB | 1,000,000,000 vs 1,073,741,824 | 7.4% |
| 1 TB | 1 TiB | 1,000,000,000,000 vs 1,099,511,627,776 | 9.95% |
Quick Tips
- 1 KB = 1,000 bytes (decimal)
- 1 KiB = 1,024 bytes (binary)
- Each step multiplies by 1,000 (decimal) or 1,024 (binary)
- The difference grows larger with bigger units