Sign, Ones', Twos' Complement & Offset Binary
Enter an integer and bit width to get sign-magnitude, ones' complement, twos' complement, offset binary and the unsigned reading at once. The reverse direction decodes a bit pattern back to a number.
Four representations
Unsigned1111 10110xFBunsigned reads = 251
Sign-magnitude1000 01010x85sign-magnitude reads = -5
Ones' complement1111 10100xFAones' complement reads = -5
Twos' complement1111 10110xFBtwos' complement reads = -5
Offset binary0111 10110x7Boffset binary reads = 123
Decode a bit pattern
The same pattern means different numbers under different encodings. Set the width and encoding.
Twos' complement is the one you meet most: 8-bit covers -128..127, 16-bit covers -32768..32767. Note that -128 has no sign-magnitude or ones' complement form at 8 bits, because the magnitude 128 does not fit — this page states that instead of printing a wrong value.
Offset binary is just the twos' complement value with the sign bit flipped; it shows up in float exponents and ADC offsets.
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