ASCII·"
34
"
0x22 · 0100010

ASCII 34 — the " character

Punctuation

" is 34 in decimal, 22 in hex and 0100010 in binary.

The marks scattered between the digits and the letters.

Seven bits

ASCII is seven bits wide, which is why there are 128 of them. The eighth bit was long left for parity.

0100010

One bit — the sixth, worth 32 — separates the cases. Off gives a capital, on gives a lowercase letter.

Kind
Punctuation
Decimal
34
Hexadecimal
0x22
Octal
042
Binary
0100010
HTML entity
"
Named entity
"
URL encoding
%22
CSS escape
\22
Short escape
\"

Only \e is missing from standard C; GCC, shells and regex engines take it.

The chart

Eight columns for the top three bits, sixteen rows for the bottom four. The capitals column sits right beside the lowercase one — that is the shape of the table.

Codes either side

How to read this

  • Add 32 to a capital and you get the lowercase letter — one bit flips.
  • Digits start at 48, so subtracting 48 from the code gives the number.
  • Holding Ctrl clears the top three bits — that is why Ctrl+I is a tab.
  • Everything under 32, plus 127, draws nothing. Those show their abbreviation instead.

Frequently asked questions

Q. What is the ASCII code for "?

Decimal 34, hex 22, octal 042, binary 0100010.

Q. How do I write " in HTML?

As ", or by name as ".

Q. How does it go in a URL?

It is encoded as %22.

Q. Does " have a partner?

No case partner: it is not a letter but a symbol.