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Number System Converter

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Math & Data

Number System Converter

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

Workspace

Run the tool here

Browser utility

Value

From base

To base

Output

Run the workspace to see the response here.

How to use

Enter the value.
Choose the source and target bases.
Copy the converted representation.

About this tool

Convert numbers between binary, octal, decimal and hexadecimal.

Number System Converter is part of the TmpMailer Math & Data set — free browser utilities that open instantly, need no account, and pair well with a temporary-email workflow when you just need a quick result.

Common use cases

Reading a memory address or colour value.
Converting a bitmask to decimal.
Teaching base conversion.

Common questions

How do I read a hex value?

Each digit represents four bits. Group pairs to map bytes, which is why colours use six hex digits.

Does it handle negative numbers?

It converts the magnitude you enter. Two's-complement representation is a separate concern.

Why does binary get long quickly?

Each decimal digit needs several bits. Hex is a compact shorthand for the same bits.

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