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Number Base Converter

Convert large integers between binary, octal, decimal and hexadecimal without precision loss.

Processed locally in your browser. Your input is not uploaded.

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How to use Number Base Converter

Choose the source base and enter integer digits, with an optional leading plus or minus sign. Results include all four bases.

Details and limits

Conversion uses BigInt rather than floating-point numbers. Prefixes, separators and fractions are not accepted. Input is limited to 4,096 characters to keep output manageable.

Practical example

Choose the source base before entering digits. Use digits without prefixes or separators; the converter accepts integers rather than fractions.

Select decimal and enter 255. The results are binary 11111111, octal 377 and hexadecimal FF.

Frequently asked questions

Why does 10 give a different value when I change the source base?

The source base determines place value: binary 10 means decimal 2, while hexadecimal 10 means decimal 16. Select the base used by your input.

Does hexadecimal output keep my leading zeros?

No. Output represents the numeric value rather than a fixed-width identifier. Add padding separately if your protocol needs a specific width.

Are negative results shown in two's complement?

No. Negative integers use a minus sign in each base. Two's-complement representation would also need a chosen bit width, which this tool does not request.