Bytes Converter
Convert between bytes, KB, MB, GB, TB, and PB in both binary and decimal systems. Enter values for instant results with step-by-step formulas.
Formula
Decimal: 1 KB = 1,000 B | Binary: 1 KiB = 1,024 B
The decimal (SI) system uses powers of 1,000: KB, MB, GB, TB, PB. The binary (IEC) system uses powers of 1,024: KiB, MiB, GiB, TiB, PiB. Storage manufacturers use decimal; operating systems often use binary but may label them with decimal prefixes.
Worked Examples
Example 1: Hard Drive Capacity Conversion
Problem: A hard drive is advertised as 2 TB (decimal). How much usable space will it show in Windows (binary)?
Solution: Decimal bytes = 2 TB x 1,000,000,000,000 = 2,000,000,000,000 bytes\nBinary GiB = 2,000,000,000,000 / 1,073,741,824 = 1,862.645 GiB\nBinary TiB = 2,000,000,000,000 / 1,099,511,627,776 = 1.819 TiB\nDifference = 2,000 GB - 1,862.645 GiB = 137.355 GiB apparent loss\nPercentage shown = 93.13% of advertised capacity
Result: A 2 TB drive shows approximately 1,862.6 GiB (1.82 TiB) in Windows, appearing 6.87% smaller than advertised.
Example 2: Download Time Estimation
Problem: How long will it take to download a 4.7 GB file on a 100 Mbps internet connection?
Solution: File size in bits = 4.7 GB x 1,000,000,000 x 8 = 37,600,000,000 bits\nConnection speed = 100 Mbps = 100,000,000 bits/second\nTime = 37,600,000,000 / 100,000,000 = 376 seconds\nMinutes = 376 / 60 = 6.27 minutes\nWith overhead (~10%): approximately 6.9 minutes
Result: Approximately 6 minutes 16 seconds theoretical, or about 7 minutes accounting for protocol overhead.
Frequently Asked Questions
How many bytes are in a kilobyte?
This depends on the system used. In the decimal (SI) system, 1 kilobyte (KB) equals exactly 1,000 bytes. In the binary system, 1 kibibyte (KiB) equals 1,024 bytes. Historically, the computer industry used KB to mean 1,024 bytes because memory is addressed in powers of 2, making 1,024 a natural unit. The International Electrotechnical Commission (IEC) standardized the binary prefixes (KiB, MiB, GiB) in 1998 to eliminate ambiguity. Despite this standard, many software applications and operating systems still use KB to mean 1,024 bytes. When precision matters, always clarify whether decimal or binary interpretation applies.
What are bits and how do they relate to bytes?
A bit (binary digit) is the smallest unit of digital information, representing a single 0 or 1. One byte consists of 8 bits and can represent 256 different values (2 to the power of 8). Network speeds are typically measured in bits per second (bps), while storage is measured in bytes. This distinction means a 100 Mbps (megabits per second) internet connection transfers approximately 12.5 MB (megabytes) per second. To convert between bits and bytes, divide bits by 8 or multiply bytes by 8. When downloading a 1 GB file on a 100 Mbps connection, the theoretical transfer time is roughly 80 seconds (1,000 MB times 8 bits divided by 100 Mbps).
Why do network speeds use bits while storage uses bytes?
This convention has historical and technical roots. Early telecommunications transmitted data one bit at a time over serial connections, so measuring in bits per second was natural for network speeds. Storage, however, organizes data in addressable bytes (8-bit groups), making bytes the logical unit for file sizes and disk capacity. The distinction persists because changing either convention would cause massive confusion across industries. This difference means you must divide your internet speed by 8 to estimate file download times. A 200 Mbps connection downloads at roughly 25 MB per second, so a 1 GB file takes about 40 seconds, not 5 seconds as one might incorrectly assume.
Does Bytes Converter work offline?
Once the page is loaded, the calculation logic runs entirely in your browser. If you have already opened the page, most calculators will continue to work even if your internet connection is lost, since no server requests are needed for computation.
How do I interpret the result?
Results are displayed with a label and unit to help you understand the output. Many calculators include a short explanation or classification below the result (for example, a BMI category or risk level). Refer to the worked examples section on this page for real-world context.
How do I get the most accurate result?
Enter values as precisely as possible using the correct units for each field. Check that you have selected the right unit (e.g. kilograms vs pounds, meters vs feet) before calculating. Rounding inputs early can reduce output precision.