Developer Tools

Number Base Converter

Convert between binary, octal, decimal, and hex

Reviewed: AnyCalc Editorial|2026-07-19|Editorial policy|About

What this calculator does

Number base converter translates numbers instantly between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Developers frequently convert between these four systems when working with low-level programming, bitwise operations, memory addresses, color codes, file permissions (octal), and network configurations (subnet masks in binary). The tool uses BigInt for handling large numbers beyond standard integer limits. Enter a number in any of the four base fields and see all other conversions update instantly. Understanding number bases is essential for debugging, reading hardware documentation, and working with binary protocols.

Edit any field to instantly convert to all other bases.

How to use

  1. 01
    Enter a number
    Type the number you want to convert in any of the four base fields.
  2. 02
    View conversions
    See the number instantly converted to binary, octal, decimal, and hexadecimal.
  3. 03
    Copy the result
    Copy the converted value in the base you need for your project.

Number Base Converter FAQ

Why do programmers use hexadecimal?
Hexadecimal is compact and maps cleanly to binary — each hex digit represents exactly 4 binary bits. This makes it ideal for representing memory addresses, color codes (#FF0000), byte values (0x7F), and binary data in a human-readable format. It is much shorter than binary: 0xFF vs 11111111.
How do I convert binary to decimal manually?
Multiply each binary digit by 2 raised to its position power (starting from 0 on the right) and sum the results. For example, binary 1011 = (1×8) + (0×4) + (1×2) + (1×1) = 11 in decimal.
What is octal used for in programming?
Octal is primarily used for Unix file permissions. Each digit represents three permission bits (read=4, write=2, execute=1). For example, chmod 755 means owner=rwx (7), group=r-x (5), others=r-x (5).

Interpret carefully

Outputs are decision-support estimates, not a substitute for professional judgment.

  • Treating Number Base Converter output as a final professional diagnosis, quote, or legal determination
  • Entering approximate values when the result is sensitive to units or precision
  • Applying the FAQ answer (“Why do programmers use hexadecimal?”) to a special case without checking assumptions

Next steps

  1. Double-check inputs against your source documents (labs, statements, specs, or notes).
  2. Confirm the method below matches your use case before you act on the number.
  3. For medical, financial, or production decisions, verify with a qualified professional.

Disclaimer: Results are informational only and do not constitute medical, financial, legal, or professional advice. Report issues: sublimernj@gmail.com