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DEVELOPER TOOL

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal.

About this tool

Type a number into any one field and see it instantly converted into the other three bases. Handy for programming, networking, and computer science work where you regularly need to translate between binary, octal, decimal, and hexadecimal.

Frequently asked questions

What characters are valid in each field?
Binary accepts only 0 and 1, octal accepts 0–7, decimal accepts 0–9, and hexadecimal accepts 0–9 and A–F (case-insensitive).
Does this support negative numbers or decimals?
No — this converts non-negative whole numbers only, which covers the vast majority of base-conversion needs in programming contexts.
Is there a maximum size?
Values are handled as standard JavaScript numbers, which are reliable up to 2^53 − 1 — comfortably enough for typical use.
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