Two's complement to decimal converter
Paste a value from a log, memory dump or processor register to see the signed number it holds.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter input format and value.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
If the first bit is 0 the value is the plain binary value. If it is 1, the value = unsigned value minus 2 to the power n, where n is the bit count.
Example
Inputs: Input format = Binary, Value = 11010110. Result: Signed decimal: -42; Bit width: 8.
11010110
-42
Limits and caveats
- The width comes from the input length, so type the leading zeros when a positive value has a wider width.
- Does not read floating-point formats.
Questions about this tool
What is 11010110 in two's complement?
Its unsigned value is 214 and the first bit is 1, so the value is 214 minus 256 = -42.
Why does the bit width matter?
1111 in 4 bits is -1, but 00001111 in 8 bits is 15. The first bit decides the sign.
How do I read a hex value like FFD6?
Choose the hex format. Each digit becomes 4 bits, the width is 16, and the result is -42.