Number Base Converter
Convert numbers between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16).
Results
| Base | Value |
|---|---|
| Binary (2) | |
| Octal (8) | |
| Decimal (10) | |
| Hexadecimal (16) |
What is a Number Base Converter?
Number base conversion translates the same numerical value between different positional numeral systems. Binary (base 2) uses only 0 and 1 — the foundation of all digital computing because electronic circuits have two states (on/off). Octal (base 8) uses digits 0–7 and was historically used in Unix file permissions and some older computing systems. Decimal (base 10) is the everyday counting system humans use. Hexadecimal (base 16) uses digits 0–9 and letters A–F and is ubiquitous in programming — representing memory addresses, colour codes (#FF5733), byte values, and binary data in a compact human-readable form.
How to Use the Number Base Converter Tool
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Enter a number in any of the four input fields: Binary, Octal, Decimal, or Hexadecimal.
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The equivalent values in all other bases are calculated and shown instantly.
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You can enter hex values with letters A–F (case-insensitive).
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For negative numbers, use two's complement in binary or a minus sign in decimal.
This number base converter updates all four representations simultaneously as you type. Runs entirely in your browser — no data is sent to any server. Useful for programming (hex colour codes, byte manipulation), networking (IP addresses), and digital electronics (binary logic).
Frequently Asked Questions
Why is hexadecimal so commonly used in programming? One hexadecimal digit represents exactly 4 binary bits. Two hex digits represent one byte (8 bits). This makes it easy to read binary data in a compact form — for example, the byte 11111111 in binary is FF in hex, much easier to read and write.
What is two's complement? Two's complement is the standard method for representing signed integers in binary. To negate a number: invert all bits, then add 1. This system makes binary arithmetic work naturally for both positive and negative numbers without special-casing zero.
How are hex colour codes structured? A CSS hex colour like #FF5733 encodes three bytes: FF is red (255), 57 is green (87), and 33 is blue (51). Each pair of hex digits (00–FF) maps to a value from 0–255 for each colour channel.
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