As character names:

U+FF71 HALFWIDTH KATAKANA LETTER A character (ア)

As raw characters:

As a string of HTML entities:

ア

Decoder output:

Byte number 1 is decimal 240, hex 0xF0, octal \360, binary 11110000
This is the first byte of a 4 byte sequence.

Byte number 2 is decimal 143, hex 0x8F, octal \217, binary 10001111
This is continuation byte 1, expecting 2 more.

Byte number 3 is decimal 189, hex 0xBD, octal \275, binary 10111101
This is continuation byte 2, expecting 1 more.

Byte number 4 is decimal 177, hex 0xB1, octal \261, binary 10110001
This is continuation byte 3, expecting 0 more.

U+FF71	HALFWIDTH KATAKANA LETTER A
	# <narrow> 30A2