Download Calculator
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Understanding Computer File Sizes
Computer file sizes depend on how much data they store. All digital data is measured in bits, short for binary digits. A bit can store a value of either 0 or 1. When 8 bits are grouped together, they form a byte.
File Size Units (Metric System)
This metric (SI) system uses prefixes like kilo, mega, and giga. In this system, 1 kB = 1,000 bytes.
| Value | Unit |
|---|---|
| 1,000 bytes | 1 kilobyte (kB) |
| 1,000 kilobytes | 1 megabyte (MB) |
| 1,000 megabytes | 1 gigabyte (GB) |
| 1,000 gigabytes | 1 terabyte (TB) |
| 1,000 terabytes | 1 petabyte (PB) |
Binary File Size Units
Historically, computers used a binary system where each unit equals 1,024 of the previous one. To avoid confusion with metric, special prefixes were introduced (KiB, MiB, GiB).
| Value | Unit |
|---|---|
| 1,024 bytes | 1 kibibyte (KiB) |
| 1,024 kibibytes | 1 mebibyte (MiB) |
| 1,024 mebibytes | 1 gibibyte (GiB) |
| 1,024 gibibytes | 1 tebibyte (TiB) |
How to Calculate Download Time
The basic formula is: Download Time = File Size ÷ Download Speed.
Example: Downloading a 400 MB file at 5 Mbps.
- Convert Size to Bits: 400 MB = 400 × 8 = 3,200 Megabits (Mb).
- Divide by Speed: 3,200 Mb ÷ 5 Mbps = 640 seconds.
- Result: 10 minutes and 40 seconds.
Frequently Asked Questions
What affects download time?
Download time mainly depends on file size and internet connection speed. Network congestion can also slow it down.
How long does it take to download a 57 GB game update?
- 1.3 hours at 100 Mbps
- 5.8 hours at 22 Mbps
- 63.3 hours at 2 Mbps