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● CONVERTERS · 9 tools

Number & Base

Binary, hexadecimal, decimal, Roman numerals, and number-to-words conversion.

9 free tools free forever runs in browser
NUMBER BASE open full tool →
255
RESULT ✓ 
hex     FF
binary  11111111
octal   377

↳ act on the page: the flagship tool is one paste away — no second click to get value.

What do you want to do?

Convert between number bases Number Base Converter → Convert to Roman numerals Roman Numeral Converter → Spell a number in words Number to Words → Convert hex to binary Hex to Binary →

Most used

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V Number Base Converter
Convert numbers between decimal, hexadecimal, binary, and octal...
V Hex to Decimal
Convert hexadecimal to decimal online for free. Paste a hex valu...
V Roman Numeral Converter
Convert between Arabic numbers and Roman numerals online for fre...

All Number & Base tools

6 more
Number to Words Hex to Binary Binary to Hex Decimal to Hex Binary to Decimal Decimal to Binary

Which number-base tool do you need?

TOOL USE WHEN RESULT
Number Base Converter You need hex, binary and octal at once All bases side by side
Roman Numeral Converter Working with Roman numerals Arabic ↔ Roman, both ways
Number to Words You need a number spelled out English words

Number & Base FAQ

Number Base Converter (binary/octal/decimal/hex at once), Roman Numerals, Number to Words, and dedicated hex/binary/decimal pair converters.
Yes — the Number Base Converter accepts base 2, 8, 10 or 16 as input and shows all four simultaneously.
Yes. All conversions run in your browser with no server round-trip.

Related Converters

Unit Converters · 24 Length, weight, temperature, speed, area, volume, and more e... Calculators · 5 Percentages, averages, aspect ratios, Unix timestamps, and c...
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