Number base converter
Convert integers between binary, octal, decimal, and hexadecimal representations. Debug color codes (#FF5733), IP bitmasks, memory addresses, and assembly coursework without mental arithmetic. Supports common bit widths (8, 16, 32) if the tool displays padding.
From
Value
Result
BIN: 11111111
OCT: 377
HEX: FF
How to convert number bases
1. Enter a number in the source base (prefix 0x for hex, 0b for binary if supported).
2. Select target base or read all bases at once.
3. Verify leading zeros for fixed-width formats (e.g. 0x0A).
4. Copy the value into code, subnet masks, or exam answers.
Base conversion examples
Hex color channel
0xFF decimal = 255 = binary 11111111 — full opacity or max red channel in #RRGGBB.
Binary to decimal
0b1010 = 10 decimal = 0xA hex. Useful for permission bit flags.
Octal (Unix permissions)
chmod 755 → rwxr-xr-x. 7=111, 5=101 in binary for owner/group/other bits.
When to convert number bases
• When you read memory dumps or register values in debuggers.
• When you translate IPv4/netmask or MAC address segments.
• When you complete CS assignments on positional notation.
When to choose something else
• When you need floating-point IEEE 754 bit layout — specialized tools.
• When you encode text as Base64 — use Base64 encoder, not radix conversion.
• When numbers exceed JavaScript safe integer — use BigInt-aware tools.
Hex and binary in programming
Bit masks use OR/AND with hex constants: flags 0x01 | 0x02. IPv6 abbreviations use hex groups. Learning to spot powers of two (0x10, 0x100) speeds reading stack traces and kernel docs.
Octal legacy in Unix
File permissions still taught in octal (755) though binary is the underlying model. Octal digits map cleanly to 3-bit groups — historical reason it persisted in chmod examples.
Frequently asked questions
What is hexadecimal?
Base 16 using digits 0–9 and A–F. Compact for binary-heavy values (1 hex digit = 4 bits).
How do I convert decimal to binary?
Repeatedly divide by 2 and collect remainders, or use this converter for instant results.
What does 0x prefix mean?
C-style hex literal prefix. 0x10 = 16 decimal, not 10.
Signed vs unsigned?
Same bit pattern interprets differently for signed two's complement — specify width and signedness in code.
Can I convert fractions?
Radix conversion of fractions is possible but non-terminating in many bases — this tool focuses on integers.
Is data uploaded?
No. Conversion runs locally.