Computer & Digital Converters
Data storage, transfer speed, number bases, ASCII, image resolution, DPI, PPI, Unix timestamps, and pixel dimensions — with the decimal SI vs binary IEC distinction handled explicitly.
Quick Converter
Convert between any decimal SI or binary IEC data storage unit.
Why Digital Units Are Confusing
Almost nobody grew up learning the difference between a megabyte and a mebibyte, and yet it shows up constantly: in the size of a USB stick, in the storage shown by an operating system, and in the download time estimates of a browser. This category exists to make those distinctions precise.
Decimal (SI) vs binary (IEC)
In 1998, the International Electrotechnical Commission introduced the binary prefixes KiB, MiB, GiB, TiB, PiB, EiB to remove ambiguity from the older kilo/mega/giga terms. The distinction:
- Decimal (SI): 1 kB = 1000 B, 1 MB = 1,000,000 B, 1 GB = 1,000,000,000 B. Used by storage manufacturers, network speeds, and most marketing.
- Binary (IEC): 1 KiB = 1024 B, 1 MiB = 1,048,576 B, 1 GiB = 1,073,741,824 B. Used internally by many operating systems, memory sizes, and precision-sensitive engineering contexts.
The ratio between the two systems grows as the magnitude increases: at the kilobyte level, decimal and binary differ by 2.4%; at the terabyte level, they differ by nearly 10%. That is why a "1 TB" drive can appear as 931 GB when read by a binary-based tool.
Number base conversions
Binary, octal, decimal, and hexadecimal are different ways to write the same integer. Programmers use hexadecimal because one hex digit maps cleanly to four binary digits. The converter in this category handles arbitrarily large integers up to JavaScript's safe integer limit (2⁵³ − 1).
Time-based digital units
Unix timestamps count seconds since 1970-01-01 00:00:00 UTC. Epoch time is the same concept under a different name. M-Convert's converter shows the equivalent UTC date and also displays the current timestamp for reference.
Image and print resolution
DPI (dots per inch) and PPI (pixels per inch) are frequently conflated. They describe different things: DPI is a printer specification, PPI is a display or image specification. When someone says "72 DPI screen resolution", they usually mean 72 PPI. The converter tool explains the distinction and converts between them using the ratio you provide.
Frequently Asked Questions
What is the difference between MB and MiB?
MB (megabyte) is a decimal SI unit equal to 1,000,000 bytes. MiB (mebibyte) is a binary IEC unit equal to 1,048,576 bytes. One MB ≈ 0.9537 MiB.
Why does my 1 TB drive show up as 931 GB?
Drive manufacturers use decimal SI (1 TB = 1,000,000,000,000 bytes). Many operating systems display binary IEC (1 TiB = 1,099,511,627,776 bytes). 1,000,000,000,000 ÷ 1,099,511,627,776 ≈ 0.9095 TiB ≈ 931 GiB.
Is a kilobit the same as a kilobyte?
No. One kilobit (kbit) is 1,000 bits, while one kilobyte (kB) is 8,000 bits, because a byte is 8 bits. Network speeds are usually quoted in bits per second; file sizes are usually quoted in bytes.
Which base conversions are supported?
Binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Custom bases between 2 and 36 are supported where the converter tool allows a base parameter.