What is Base32: Encoding, Decoding, Characters and Alternatives
This blog post will delve into the intricacies of Base32, its character set, and the process of encoding and decoding. We’ll also explore some alternatives to Base32, such as Z-Base32, Base32Hex, and Crockford’s Base32, providing a comprehensive understanding of these fascinating data representation methods.
What is Base32?
Base32 encoding serves as a valuable binary-to-text encoding technique, allowing for the representation of binary data in a more readable and manageable format using a set of 32 characters. Unlike raw binary data, which can include unusual or non-printable characters that can cause problems during transmission or storage, Base32 encoding ensures that data remains compatible and intact.
By converting binary data into a set of 32 printable characters, Base32 encoding helps avoid issues caused by non-printable characters present in raw binary data. This encoding scheme ensures that data can be transmitted or stored more reliably in systems that may have difficulties handling raw binary data. As a result, Base32 encoding is widely used in various applications, including data transfer, data encoding, and creating human-readable representations of binary data.
Here’s a breakdown about Base32:
Binary to Text: Converts streams of 0s and 1s (binary data) into a shorter, text-based string using letters and numbers.
More Compact: Compared to Base64, Base32 results in a slightly smaller encoded string due to using fewer characters.
URL-Friendly: The character set avoids symbols like “+” and “/” that might cause issues in URLs, making it suitable for embedding data in web addresses.
Less Common: Not as widely used as Base64, so decoding compatibility might be more limited.
Security Note: Similar to Base64, Base32 encoding doesn’t encrypt data. Anyone can decode it back to the original binary form.
The key to Base32 lies in its character set. This encoding scheme uses a specific set of 32 characters, which include uppercase letters A through Z and the digits 2 through 7. This character set was designed with careful consideration to avoid ambiguity and ensure that the encoded data can be accurately decoded.
Here are the 32 characters used in Base32:
Binary
Decimal
Base32
00000
0
A
00001
1
B
00010
2
C
00011
3
D
00100
4
E
00101
5
F
00110
6
G
00111
7
H
01000
8
I
01001
9
J
01010
10
K
01011
11
L
01100
12
M
01101
13
N
01110
14
O
01111
15
P
10000
16
Q
10001
17
R
10010
18
S
10011
19
T
10100
20
U
10101
21
V
10110
22
W
10111
23
X
11000
24
Y
11001
25
Z
11010
26
2
11011
27
3
11100
28
4
11101
29
5
11110
30
6
11111
31
7
How to Encode and Decode Using Base32
Encoding data with Base32 is a straightforward process. You take your binary data and convert it into a series of 5-bit chunks. Each 5-bit chunk is then mapped to the corresponding character from the Base32 character set. This results in a text string that is safe for transmission and storage.
Decoding Base32 is the reverse process. You take the Base32-encoded text and convert it back into its original binary form, using the character set as a reference.
Encoding Example
Let’s say you have the binary data: 010000100011001100110010, and you want to encode it in Base32. Here’s how it’s done:
Divide the binary data into 5-bit chunks:
01000, 01000, 11001, 10011, 0010
Map each 5-bit chunk to the corresponding Base32 character:
I, I, Z, T, E
So, the Base32-encoded representation of the binary data is IIZTE===.
If you’re wondering how those few equals signs ended up at the end of the result, here’s a little help:
If the last 5-byte block contains 1 byte of input data, add 4 zero bytes. Then, encode it as a regular block and replace the last 6 characters with 6 equal signs (======).
If the last 5-byte block holds 2 bytes of input data, add 3 zero bytes. After encoding it as a standard block, change the last 4 characters to 4 equal signs (====).
If the last 5-byte block includes 3 bytes of input data, add 2 zero bytes. Encode it as a regular block and replace the last 3 characters with 3 equal signs (===).
If the last 5-byte block has 4 bytes of input data, add 1 zero byte. After encoding it as a normal block, replace the last 1 character with 1 equal sign (=).
The Base32 is a well-established method with its own character set and encoding rules. However, there are alternative encoding schemes that cater to specific needs and use cases. In this chapter, we will delve into three noteworthy Base32 alternatives: Z-Base32, Base32Hex, and Crockford’s Base32.
Z-Base32, is an alternative encoding scheme with a few key distinctions from traditional Base32. It was designed to improve human readability while maintaining data integrity. It has an extended character set:Z-Base32 uses a character set that includes lowercase letters and numbers.
Base32Hex is another variant of Base32 encoding that primarily differs in its character set. It uses a character set that includes only the digits 0-9 and the uppercase letters A through V, which simplifies the encoding process and increases data density.
Crockford’s Base32, created by Douglas Crockford, is an encoding scheme optimized for use in URLs, filenames, and case-insensitive environments. It uses a character set consisting of ten digits and twenty-two letters (excluding ‘I’, ‘L’, ‘O’, and ‘U’ to avoid visual ambiguity).
Here is a concrete comparison of the character sets of the four variations.
Base32
Z-Base32
Base32Hex
Crockford’s Base32
A
y
0
0
B
b
1
1
C
n
2
2
D
d
3
3
E
r
4
4
F
f
5
5
G
g
6
6
H
8
7
7
I
e
8
8
J
j
9
9
K
k
A
A
L
m
B
B
M
c
C
C
N
p
D
D
O
q
E
E
P
x
F
F
Q
o
G
G
R
t
H
H
S
1
I
J
T
u
J
K
U
w
K
M
V
i
L
N
W
s
M
P
X
z
N
Q
Y
a
O
R
Z
3
P
S
2
4
Q
T
3
5
R
V
4
h
S
W
5
7
T
X
6
6
U
Y
7
9
V
Z
Base32 Examples
Here is some text and its Base32 encoded version to give you a better idea of what Base64 is and how it changes the visual representation of the data.
