A number base (or radix) defines how many unique digits a positional numeral system uses. Base 2 (binary) uses only 0 and 1. Base 8 (octal) uses 0–7. Base 10 (decimal) is the everyday system using 0–9. Base 16 (hexadecimal) uses 0–9 plus A–F, where A=10 and F=15.
Repeatedly divide the decimal number by 2 and record the remainders from bottom to top. For example, 42 ÷ 2 gives remainders 0,1,0,1,0,1 — read upward as 101010. This tool does all of this instantly using JavaScript's native parseInt and Number.toString(2).
Each hex digit maps exactly to 4 binary bits (a "nibble"), so a byte (8 bits) is always two hex digits. This makes hex very compact and easy to read when working with memory addresses, color codes, bitmasks, and network packet data.
Binary accepts only 0 and 1. Octal accepts digits 0–7. Decimal accepts digits 0–9. Hexadecimal accepts 0–9 and A–F (case-insensitive). The tool validates your input in real time and shows an error if you enter an invalid character.
Bit length is the number of binary digits needed to represent the number — essentially the length of the binary output. For example, the decimal number 255 requires 8 bits. This is useful for understanding memory usage and data type sizing.
The tool uses JavaScript's standard Number type (64-bit IEEE 754 floating point), which safely represents integers up to 2^53 − 1 (9,007,199,254,740,991). For most practical use cases this is more than sufficient. Very large integers may lose precision beyond this limit.
Uppercase (A–F) is the conventional format in most technical contexts — memory dumps, color codes, CPU instruction sets, and network protocols all use uppercase hex. The tool follows this convention for readability and consistency.
No. All conversions happen entirely inside your browser using JavaScript. No data is transmitted over the network at any point.
The Bit Breakdown panel displays each binary digit of the result with its positional index (bit 0 = least significant). It is helpful for understanding bitwise operations, flag registers, and binary arithmetic.
Yes, completely free — no account, no sign-up, no usage limits, forever.
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