Complete URL Encoded Characters Table (ASCII + Unicode)

ASCII Control and Special Characters

ASCII characters in the range 0-31 and character 127 are control characters. These are not printable and must always be percent-encoded in URLs. The most commonly encountered control characters in URL contexts are the space (ASCII 32), horizontal tab (ASCII 9), and newline characters (ASCII 10 and 13).

According to RFC 3986, any octet that is not an unreserved character, a reserved character used for its reserved purpose, or a percent-encoded triplet must be percent-encoded. In practice, this means most non-alphanumeric characters should be encoded in URI components.

Character	ASCII Code	URL Encoded	Description
(tab)	9	%09	Horizontal Tab
(LF)	10	%0A	Line Feed
(CR)	13	%0D	Carriage Return
(space)	32	%20	Space

Printable ASCII Characters

Below is a complete reference of all printable ASCII characters (codes 32-126) and their URL-encoded forms. Characters marked as "unreserved" in RFC 3986 do not require encoding. Reserved characters must be encoded when used outside their reserved purpose.

Character	ASCII	Hex	URL Encoded	Type
(space)	32	20	%20	Special
!	33	21	%21	Reserved
"	34	22	%22	Unsafe
#	35	23	%23	Reserved
$	36	24	%24	Reserved
%	37	25	%25	Special
&	38	26	%26	Reserved
'	39	27	%27	Reserved
(	40	28	%28	Reserved
)	41	29	%29	Reserved
*	42	2A	%2A	Reserved
+	43	2B	%2B	Reserved
,	44	2C	%2C	Reserved
-	45	2D	%2D	Unreserved
.	46	2E	%2E	Unreserved
/	47	2F	%2F	Reserved
0-9	48-57	30-39	Not required	Unreserved
:	58	3A	%3A	Reserved
;	59	3B	%3B	Reserved
<	60	3C	%3C	Unsafe
=	61	3D	%3D	Reserved
>	62	3E	%3E	Unsafe
?	63	3F	%3F	Reserved
@	64	40	%40	Reserved
A-Z	65-90	41-5A	Not required	Unreserved
[	91	5B	%5B	Reserved
\	92	5C	%5C	Unsafe
]	93	5D	%5D	Reserved
^	94	5E	%5E	Unsafe
_	95	5F	%5F	Unreserved
`	96	60	%60	Unsafe
a-z	97-122	61-7A	Not required	Unreserved
{	123	7B	%7B	Unsafe
|	124	7C	%7C	Unsafe
}	125	7D	%7D	Unsafe
~	126	7E	%7E	Unreserved

Common Unicode Encodings

Unicode characters are first encoded to their UTF-8 byte sequence, then each byte is individually percent-encoded. Multi-byte characters produce multiple percent-encoded triplets.

Character	Description	UTF-8 Bytes	URL Encoded
a with umlaut	Latin Small Letter A with Diaeresis	C3 A4	%C3%A4
n with tilde	Latin Small Letter N with Tilde	C3 B1	%C3%B1
e with acute	Latin Small Letter E with Acute	C3 A9	%C3%A9
u with umlaut	Latin Small Letter U with Diaeresis	C3 BC	%C3%BC
Euro sign	Euro Sign	E2 82 AC	%E2%82%AC
Pound sign	Pound Sign	C2 A3	%C2%A3
Yen sign	Yen Sign	C2 A5	%C2%A5
CJK zhong	CJK Unified Ideograph (middle)	E4 B8 AD	%E4%B8%AD
Cyrillic Ya	Cyrillic Capital Letter Ya	D0 AF	%D0%AF
Arabic Ba	Arabic Letter Ba	D8 A8	%D8%A8

How Multi-Byte Characters Are Encoded

UTF-8 uses a variable-length encoding scheme. Characters in the ASCII range (0-127) use one byte. Characters outside this range use two to four bytes. When percent-encoding, each byte of the UTF-8 representation becomes a separate %XX triplet.

Two-byte characters (U+0080 to U+07FF): These include most Latin extended, Greek, Cyrillic, and Arabic characters. For example, the German letter sharp s (U+00DF) encodes to UTF-8 bytes C3 9F, which becomes %C3%9F.

Three-byte characters (U+0800 to U+FFFF): These include CJK characters, most symbols, and the Basic Multilingual Plane. For example, the Japanese hiragana character (U+3042) encodes to UTF-8 bytes E3 81 82, which becomes %E3%81%82.

Four-byte characters (U+10000 to U+10FFFF): These include emoji and supplementary characters. For example, the grinning face emoji (U+1F600) encodes to UTF-8 bytes F0 9F 98 80, which becomes %F0%9F%98%80.

// JavaScript demonstration of multi-byte encoding
console.log(encodeURIComponent('u with umlaut'));
// Two bytes: "%C3%BC"

console.log(encodeURIComponent('CJK char'));
// Three bytes: "%E4%B8%AD"

console.log(encodeURIComponent('emoji'));
// Four bytes: "%F0%9F%98%80"

// You can verify by decoding
console.log(decodeURIComponent('%C3%BC'));  // u with umlaut
console.log(decodeURIComponent('%E4%B8%AD')); // CJK char