66
B
0x42 · 1000010
ASCII 66 — the B character
Uppercase
B is 66 in decimal, 42 in hex and 1000010 in binary. It sits 32 away from b.
A starts at 65 and twenty-six letters follow.
Seven bits
ASCII is seven bits wide, which is why there are 128 of them. The eighth bit was long left for parity.
1000010
One bit — the sixth, worth 32 — separates the cases. Off gives a capital, on gives a lowercase letter.
- Kind
- Uppercase
- Decimal
- 66
- Hexadecimal
- 0x42
- Octal
- 102
- Binary
- 1000010
- HTML entity
- B
- URL encoding
- B
- CSS escape
- \42
- With Ctrl held
- STX (2)
- Case pair
- b (98)
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.
0NUL1SOH2STX3ETX4EOT5ENQ6ACK7BEL8BS9HT10LF11VT12FF13CR14SO15SI16DLE17DC118DC219DC320DC421NAK22SYN23ETB24CAN25EM26SUB27ESC28FS29GS30RS31US32SP33!34"35#36$37%38&39'40(41)42*43+44,45-46.47/48049150251352453554655756857958:59;60<61=62>63?64@65A66B67C68D69E70F71G72H73I74J75K76L77M78N79O80P81Q82R83S84T85U86V87W88X89Y90Z91[92\93]94^95_96`97a98b99c100d101e102f103g104h105i106j107k108l109m110n111o112p113q114r115s116t117u118v119w120x121y122z123{124|125}126~127DEL
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 B?
Decimal 66, hex 42, octal 102, binary 1000010.
Q. How do I write B in HTML?
As B.
Q. How does it go in a URL?
It can stay as it is — this character needs no encoding.
Q. Does B have a partner?
b — the codes are 32 apart.