Base64 Encoder & Decoder

Our professional Base64 tool handles everything from image previews to JWT inspection. Process data 100% in your browser for maximum security. Encode images directly into **HTML & CSS snippets**, decode **JWT tokens** instantly, or convert plain text to URL-safe Base64 format—all processed safely in your browser.

100% Client-Side Instant Results

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Supports JPG, PNG, WebP, SVG

IMAGE BASE64 OUTPUT0 B

Deep Dive: Base64 Mechanics

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It is commonly used to transfer data over channels that only support text, like email or certain API headers.

Yes. Our tool is 100% client-side. Your JWT tokens and private data are never sent to our servers; the decoding happens entirely within your browser.

Standard Base64 uses "+" and "/" which have special meanings in URLs. URL-safe Base64 replaces these with "-" and "_" respectively, making the output safe for use in query parameters.

No. Base64 encoding actually increases file size by approximately 33%. It should only be used for small images (like icons) where the benefit of reducing HTTP requests outweighs the extra bandwidth.

Developer Tips

Use **URL-safe Base64** when passing encoded data in URL parameters.
Base64 strings are ~33% larger than the original binary data.
For JWTs, we only decode the Header and Payload; the Signature is verified on the server.

Base64 Character Reference Table

Index (6-bit Value)	Binary	Character (Base64)	Decimal Equivalent
0	`000000`	A	65
1	`000001`	B	66
2	`000010`	C	67
3	`000011`	D	68
4	`000100`	E	69
5	`000101`	F	70
6	`000110`	G	71
7	`000111`	H	72
8	`001000`	I	73
9	`001001`	J	74
10	`001010`	K	75
11	`001011`	L	76
12	`001100`	M	77
13	`001101`	N	78
14	`001110`	O	79
15	`001111`	P	80
16	`010000`	Q	81
17	`010001`	R	82
18	`010010`	S	83
19	`010011`	T	84
20	`010100`	U	85
21	`010101`	V	86
22	`010110`	W	87
23	`010111`	X	88
24	`011000`	Y	89
25	`011001`	Z	90
26	`011010`	a	97
27	`011011`	b	98
28	`011100`	c	99
29	`011101`	d	100
30	`011110`	e	101
31	`011111`	f	102
32	`100000`	g	103
33	`100001`	h	104
34	`100010`	i	105
35	`100011`	j	106
36	`100100`	k	107
37	`100101`	l	108
38	`100110`	m	109
39	`100111`	n	110
40	`101000`	o	111
41	`101001`	p	112
42	`101010`	q	113
43	`101011`	r	114
44	`101100`	s	115
45	`101101`	t	116
46	`101110`	u	117
47	`101111`	v	118
48	`110000`	w	119
49	`110001`	x	120
50	`110010`	y	121
51	`110011`	z	122
52	`110100`	0	48
53	`110101`	1	49
54	`110110`	2	50
55	`110111`	3	51
56	`111000`	4	52
57	`111001`	5	53
58	`111010`	6	54
59	`111011`	7	55
60	`111100`	8	56
61	`111101`	9	57
62	`111110`	+	43
63	`111111`	/	47
64		=	61