What does Number Base Converter do?

Convert between binary, octal, decimal and hex, including very large numbers. It belongs to the Math Tools group and runs entirely in your browser — nothing you type or paste is uploaded.

Are calculations accurate?

All calculation tools are thoroughly tested for accuracy and reliability.

What types of calculators are there?

Percentage calculator, date calculator, BMI calculator, mortgage calculator and more.

Number Base Converter

Convert between binary, octal, decimal and hex, including very large numbers.

Back to tools

Tool Panel

Processed locally

BinaryBASE-2

OctalBASE-8

DecimalBASE-10

HexadecimalBASE-16

Clear the other fields when this one is empty

About base conversion

Base conversion is a foundational idea in computer science. The common bases are:

Binary: base 2, using 0 and 1 — how computers store numbers.
Octal: base 8, using 0-7 — common for Unix file permissions.
Decimal: base 10, the everyday counting system.
Hexadecimal: base 16, using 0-9 and A-F — common for memory addresses and colour codes.

About Number Base Converter

Converts between binary, octal, decimal, hex and any base from 2 to 36, using BigInt so large values stay exact.

1
One-click operation for fast formatting or compression
2
Accurate numerical calculations you can trust
3
Support for multiple calculation types

Related tools

View all

Math Tools

BMI Calculator

Work out your body mass index and what the range means.

Math Tools

Mortgage Calculator

Work out monthly repayments and total interest on a loan.

Math Tools

Percentage Calculator

Work out percentages, ratios and growth rates.

Math Tools

Date Difference

Count the days, months or years between two dates.

Math Tools

Timestamp Converter

Convert between Unix timestamps and readable dates.

Math Tools