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CONVERTERS

Number Base Converter

Enter a number in binary, octal, decimal, or hexadecimal and see all representations update with BigInt precision.

Tool statusRuns in your browser
Preview

Input

Results

BIN
11111111
OCT
377
DEC
255
HEX
FF

How it works

  1. Enter your input

    Fill in the values, paste your text, or upload the file this tool works with.

  2. See results instantly

    Most tools update live as you type; a few use a single button. Either way, the result appears right on this page.

  3. Use your results

    Copy, download, or share what the tool produces — you're always in control of the output.

Privacy and processing — Runs locally in your browser. This tool does not upload your input.

What is Number Base Converter?

Convert integers between binary, octal, decimal, and hexadecimal, including large values that need BigInt precision.

UNDERSTAND THE TOOL

How to convert number bases

Accepted input

Choose the base of the number you are entering. Spaces and underscores are ignored, optional 0b, 0o, and 0x prefixes are accepted, and negative integers keep their sign.

Output formats

The result panel shows the same integer in BIN, OCT, DEC, and HEX. Hexadecimal output uses uppercase A-F for readability.

What it does not handle

  • Fractional values or decimal points.
  • Scientific notation such as 1e6.
  • Two's-complement width calculations for signed binary storage.

Conversion notes

The converter treats input as an integer value, not as a fixed-width memory representation. Add your own byte width when you need two's-complement interpretation.

Frequently Asked Questions

Can I paste 0xFF or 0b1010?

Yes. Prefixes such as 0x, 0o, and 0b are stripped after the sign, as long as the selected input base matches the digits.

Why is my number rejected?

At least one digit is outside the selected base, such as 2 in binary or G in hexadecimal.

Does it support very large integers?

Yes. The conversion uses BigInt, so values larger than JavaScript's normal safe integer range remain precise.

Does it convert fractions?

No. This tool is for whole integers only.

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