87

URL Encoding in HTTP

HTTP URLs sent over the internet using the ASCII character-set. In URL-encoding, the following things are performed:

1. Convert all the “unsafe” characters to “%xx”, where xx is the ASCII value of the character in hexadecimal.

2. All the spaces changes into pluses.

3. String the name and value together with = and &

Example

4. For POST submission, the string will be our message body, and for GET submission, the query string will be our message body.

The ASCII symbols of the characters and their replacements are shown in the following table. These replacements of the symbol can be used in the URL before passing it to the server:

Symbol	ASCII	Replacement
Backspace	08	%08
tab	09	%09
linefeed	10	%0A
creturn	13	%0D
space	32	%20 or +
!	33	%21
“	34	%22
#	35	%23
$	36	%24
%	37	%25
&	38	%26
‘	39	%27
(	40	%28
)	41	%29
*	42	*
+	43	%2B
‘	44	%2C
–	45	–
.	46	.
/	47	%2F
0	48	0
1	49	1
2	50	2
3	51	3
4	52	4
5	53	5
6	54	6
7	55	7
8	56	8
9	57	9
:	58	%3A
;	59	%3B
<	60	%3C
=	61	%3D
>	62	%3E
?	63	%3F
@	64	%40
A	65	A
B	66	B
C	67	C
D	68	D
E	69	E
F	70	F
G	71	G
H	72	H
I	73	I
J	74	J
K	75	K
L	76	L
M	77	M
N	78	N
O	79	O
P	80	P
Q	81	Q
R	82	R
S	83	S
T	84	T
U	85	U
V	86	V
W	87	W
X	88	X
Y	89	Y
Z	90	Z
[	91	%5B
	92	%5C
]	93	%5D
^	94	%5E
_	95	_
.	96	%60
a	97	a
b	98	b
c	99	c
d	100	d
e	101	e
f	102	f
g	103	g
h	104	h
i	105	i
j	106	j
k	107	k
l	108	l
m	109	m
n	110	n
o	111	0
p	112	p
q	113	q
r	114	r
s	115	s
t	116	t
u	117	u
v	118	v
w	119	w
x	120	x
y	121	y
z	122	z
{	123	%7B
|	124	%7C
}	125	%7D
~	126	%7E
	127	%7F
	> 127	Encode with “%xx”, where “xx” is the ASCII value of the character, in hexadecimal

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