ASCII Code 21

This table contains detailed information for ASCII code #21. For this entry, you’ll find:

Name:NAK - Negative AcknowledgementThe conventional name for control characters
Decimal:21The base‑10 number
Octal:025The base‑8 representation (three digits)
Hexadecimal:15The base‑16 representation (two digits, uppercase)
Binary:00010101The 8‑bit binary representation