Hex Reference
0x21 in Binary = 00100001
Hex 0x21 converts to binary 00100001. Decimal: 33. Octal: 41. ASCII character: "!".
Quick Answer
Hex
21
Binary
00100001
Decimal
33
Octal
41
ASCII Character
"!"
How to Convert 0x21 to Binary — Step by Step
1
Separate the two hex digits
0x21 = high nibble 2 + low nibble 1
2
Convert each digit to 4 binary bits
Hex 2 = 0010 (decimal 2)
Hex 1 = 0001 (decimal 1)
3
Concatenate the 4-bit groups
0010 + 0001 = 00100001
0x21 in All Number Systems
| Hex (Base 16) | 21 (0x21) |
| Binary (Base 2) | 00100001 (0010 0001) |
| Decimal (Base 10) | 33 |
| Octal (Base 8) | 41 |
| ASCII | "!" |
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