HTML5 - URL Encoding

URL encoding is the practice of translating unprintable characters or characters with special meaning within URLs to a representation that is unambiguous and universally accepted by web browsers and servers. These characters include:

• ASCII control characters - Unprintable characters typically used for output control. Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal). A complete encoding table is given below.
• Non-ASCII control characters - These are characters beyond the ASCII character set of 128 characters. This range is part of the ISO-Latin character set and ncludes the entire "top half" of the ISO-Latin set 80-FF hex (128-255 decimal). A complete encoding table is given below.
• Reserved characters - These are special characters such as the dollar sign, ampersand, plus, common, forward slash, colon, semi-colon, equals sign, question mark, and "at" symbol. All of these can have different meanings inside a URL so need to be encoded. A complete encoding table is given below.
• Unsafe characters - These are space, quotation marks, less than symbol, greater than symbol, pound character, percent character, Left Curly Brace, Right Curly Brace , Pipe, Backslash, Caret, Tilde, Left Square Bracket , Right Square Bracket, Grave Accent. These character present the possibility of being misunderstood within URLs for various reasons. These characters should also always be encoded. A complete encoding table is given below.

The encoding notation replaces the desired character with three characters: a percent sign and two hexadecimal digits whose correspond to the position of the character in the ASCII character set.

Example:

One of the most common special characters is the space. You can't type a space in a URL directly. A space position in the character set is 20 hexadecimal. So you can use %20 in place a space when passing your request to the server.

http://www.example.com/new%20pricing.html

This URL actually retrieves a document named new pricing.html from the www.example.com

ASCII control characters encoding

This includes the encoding for character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal)

Decimal	Hex Value	Character	URL Encode
0	00
1	01		%01
2	02		%02
3	03		%03
4	04		%04
5	05		%05
6	06		%06
7	07		%07
8	08	backspace	%08
9	09	tab	%09
10	0a	linefeed	%0a
11	0b		%0b
12	0c		%0c
13	0d	carriage return	%0d
14	0e		%0e
15	0f		%0f
16	10		%10
17	11		%11
18	12		%12
19	13		%13
20	14		%14
21	15		%15
22	16		%16
23	17		%17
24	18		%18
25	19		%19
26	1a		%1a
27	1b		%1b
28	1c		%1c
29	1d		%1d
30	1e		%1e
31	1f		%1f
127	7f		%7f

Non-ASCII control characters encoding

This includes the encoding for the entire "top half" of the ISO-Latin set 80-FF hex (128-255 decimal.)

Decimal	Hex Value	Character	URL Encode
128	80	€	%80
129	81		%81
130	82	‚	%82
131	83	ƒ	%83
132	84	„	%84
133	85	…	%85
134	86	†	%86
135	87	‡	%87
136	88	ˆ	%88
137	89	‰	%89
138	8a	Š	%8a
139	8b	‹	%8b
140	8c	Œ	%8c
141	8d		%8d
142	8e	Ž	%8e
143	8f		%8f
144	90		%90
145	91	‘	%91
146	92	’	%92
147	93	“	%93
148	94	”	%94
149	95	•	%95
150	96	–	%96
151	97	—	%97
152	98	˜	%98
153	99	™	%99
154	9a	š	%9a
155	9b	›	%9b
156	9c	œ	%9c
157	9d		%9d
158	9e	ž	%9e
159	9f	Ÿ	%9f
160	a0		%a0
161	a1	¡	%a1
162	a2	¢	%a2
163	a3	£	%a3
164	a4	¤	%a4
165	a5	¥	%a5
166	a6	¦	%a6
167	a7	§	%a7
168	a8	¨	%a8
169	a9	©	%a9
170	aa	ª	%aa
171	ab	«	%ab
172	ac	¬	%ac
173	ad	­	%ad
174	ae	®	%ae
175	af	¯	%af
176	b0	°	%b0
177	b1	±	%b1
178	b2	²	%b2
179	b3	³	%b3
180	b4	´	%b4
181	b5	µ	%b5
182	b6	¶	%b6
183	b7	·	%b7
184	b8	¸	%b8
185	b9	¹	%b9
186	ba	º	%ba
187	bb	»	%bb
188	bc	¼	%bc
189	bd	½	%bd
190	be	¾	%be
191	bf	¿	%bf
192	c0	À	%c0
193	c1	Á	%c1
194	c2	Â	%c2
195	c3	Ã	%c3
196	c4	Ä	%c4
197	c5	Å	%c5
198	c6	Æ	%v6
199	c7	Ç	%c7
200	c8	È	%c8
201	c9	É	%c9
202	ca	Ê	%ca
203	cb	Ë	%cb
204	cc	Ì	%cc
205	cd	Í	%cd
206	ce	Î	%ce
207	cf	Ï	%cf
208	d0	Ð	%d0
209	d1	Ñ	%d1
210	d2	Ò	%d2
211	d3	Ó	%d3
212	d4	Ô	%d4
213	d5	Õ	%d5
214	d6	Ö	%d6
215	d7	×	%d7
216	d8	Ø	%d8
217	d9	Ù	%d9
218	da	Ú	%da
219	db	Û	%db
220	dc	Ü	%dc
221	dd	Ý	%dd
222	de	Þ	%de
223	df	ß	%df
224	e0	à	%e0
225	e1	á	%e1
226	e2	â	%e2
227	e3	ã	%e3
228	e4	ä	%e4
229	e5	å	%e5
230	e6	æ	%e6
231	e7	ç	%e7
232	e8	è	%e8
233	e9	é	%e9
234	ea	ê	%ea
235	eb	ë	%eb
236	ec	ì	%ec
237	ed	í	%ed
238	ee	î	%ee
239	ef	ï	%ef
240	f0	ð	%f0
241	f1	ñ	%f1
242	f2	ò	%f2
243	f3	ó	%f3
244	f4	ô	%f4
245	f5	õ	%f5
246	f6	ö	%f6
247	f7	÷	%f7
248	f8	ø	%f8
249	f9	ù	%f9
250	fa	ú	%fa
251	fb	û	%fb
252	fc	ü	%fc
253	fd	ý	%fd
254	fe	þ	%fe
255	ff	ÿ	%ff

Reserved characters encoding

Following is the table to be used to encode reserved characters.

Decimal	Hex Value	Char	URL Encode
36	24	$	%24
38	26	&	%26
43	2b	+	%2b
44	2c	,	%2c
47	2f	/	%2f
58	3a	:	%3a
59	3b	;	%3b
61	3d	=	%3d
63	3f	?	%3f
64	40	@	%40

Unsafe characters encoding

Following is the table to be used to encode unsafe characters.

Decimal	Hex Value	Char	URL Encode
32	20	space	%20
34	22	"	%22
60	3c	<	%3c
62	3e	>	%3e
35	23	#	%23
37	25	%	%25
123	7b	{	%7b
125	7d	}	%7d
124	7c	|	%7c
92	5c	\	%5c
94	5e	^	%5e
126	7e	~	%7e
91	5b	[	%5b
93	5d	]	%5d
96	60	`	%60