ASCII 7
ASCII 7 is Bell — the control character BEL.
Every representation
| Character | BEL (not printable) |
| Name | Bell |
| Decimal | 7 |
| Hexadecimal | 0x07 |
| Octal | 0007 |
| Binary | 00000111 |
| HTML entity |  |
| Escape sequence | \\a |
| Unicode | U+0007 |
| Keyboard | Ctrl+G |
| Group | Control character |
What it is for
Rang the physical bell on a teletype. Terminals still beep or flash on receiving it, which is why printf "\\a" makes a noise and why a stray byte in a binary file can make your terminal chirp.
Where the number comes from
Codes 0 to 31 were reserved for control: instructions to a teleprinter rather than characters to print. Code 7 is Ctrl+G because the Ctrl key was originally wired to clear the top two bits of whatever you typed, mapping the letter G at 71 down to 7.
Frequently asked questions
What is ASCII 7?
Bell (BEL), a control character. In hexadecimal it is 0x07, in octal 0007, and in binary 00000111.
How do I type ASCII 7?
Press Ctrl+G in a terminal. In a string literal you can write it as \\a or \\x07 in most languages.
Is ASCII 7 printable?
No. Codes 0 to 31 and 127 are control characters — they were instructions to a teleprinter rather than marks on paper, and most terminals show nothing for them.
Nearby codes
- ASCII 0 — NUL
- ASCII 1 — SOH
- ASCII 2 — STX
- ASCII 3 — ETX
- ASCII 4 — EOT
- ASCII 5 — ENQ
- ASCII 6 — ACK
- ASCII 8 — BS
- ASCII 9 — HT
- ASCII 10 — LF
- ASCII 11 — VT
- ASCII 12 — FF
- ASCII 13 — CR
- ASCII 14 — SO
Full ASCII table · Text to binary converter · Number base converter