Number Base Converter

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal. The result updates as you type.

Free
No signup
Instant
Private
Input
0 words • 0 characters • 0 without spaces • 0 lines
Conversion
Output
0 words • 0 characters • 0 without spaces • 0 lines

Private by design

This conversion runs entirely in your browser. Your text is not sent to a server.

Tip

Spaces are ignored. Hex digits A–F are accepted in either case. The output is uppercase.

How to convert with Number Base Converter

  1. Paste a number in the source base (decimal, binary, octal, or hex).

  2. The converted value updates as you type — nothing is uploaded.

  3. Choose a conversion such as Decimal → Hex or Hex → Binary.

  4. Copy the result, or use it as the next input.

When should you use it?

  • Bases

    Move between binary, octal, decimal, and hexadecimal in one step.

  • Hex

    Read or write 0x-style values without a calculator.

  • Bits

    See the binary form of a decimal or hex integer.

  • Stays here

    Conversion runs in this tab. Nothing is uploaded.

Your numbers stay private.

Base conversion runs entirely in your browser. Values never leave this tab.

Learn more about privacy →

About converting number bases in the browser

Number Base Converter moves an integer between decimal, binary, octal, and hexadecimal as you type. Spaces are ignored. Hex digits A–F are accepted in either case; output is uppercase. This is integer conversion, not UTF-8 hex dumps — Hex Encode / Decode is the sibling for text bytes. It is not IEEE floating point and not two’s-complement bitfields beyond what the integer parser accepts.

Worked example: 255 decimal is FF hex and 11111111 binary. 0x10 as hex input is 16 decimal. Invalid digits for the source base show an error instead of a guessed value.

Related: Color Converter for #RRGGBB, Hash Generator for digests, Hex Encode for strings. Nothing is uploaded. Pick a conversion such as Decimal → Hex on the page; Convert to is not a second integer.

Related developer tools

Number Base Converter examples

Decimal → Hex

Input
255
Output
FF

Decimal → Binary

Input
255
Output
11111111

Hex → Decimal

Input
FF
Output
255

Base comparison

ConversionExampleTypical use
Decimal → HexFFCSS colors, memory dumps, and byte values
Decimal → Binary11111111Bit flags, masks, and low-level checks
Hex → Decimal255Turn a hex dump back into a decimal integer

Number Base Converter FAQ

Binary, octal, decimal, and hexadecimal. Choose a conversion (for example Decimal → Hex). The result updates as you type. Spaces are ignored; hex letters can be upper or lower case.