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Base 11 to Base 21

Base 11 to Base 21 Converter

Enter a number in base 11 below to convert it to base 21 instantly.

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About These Bases

Base 11

In base 11, each digit position represents a power of 11: the rightmost digit counts individual ones, the next counts groups of 11, the next counts groups of 11×11, and so on — the same place-value idea as base 10, just with 11 distinct digits instead of ten.

Base 21

Base 21 works the same way: the rightmost digit counts ones, the next counts groups of 21, the next counts groups of 21×21, and so on, using 21 distinct digits.

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Quick Reference Table
Base 10 Base 11 Base 21
1 1 1
2 2 2
3 3 3
4 4 4
5 5 5
6 6 6
7 7 7
8 8 8
9 9 9
10 A A
11 10 B
12 11 C
13 12 D
14 13 E
15 14 F
16 15 G
17 16 H
18 17 I
19 18 J
20 19 K
21 1A 10
22 20 11
23 21 12
24 22 13
25 23 14
26 24 15
27 25 16
28 26 17
29 27 18
30 28 19
31 29 1A
32 2A 1B
33 30 1C
34 31 1D
35 32 1E
36 33 1F
37 34 1G
38 35 1H
39 36 1I
40 37 1J
41 38 1K
42 39 20
43 3A 21
44 40 22
45 41 23
46 42 24
47 43 25
48 44 26
49 45 27
50 46 28
51 47 29
52 48 2A
53 49 2B
54 4A 2C
55 50 2D
56 51 2E
57 52 2F
58 53 2G
59 54 2H
60 55 2I
61 56 2J
62 57 2K
63 58 30
64 59 31
70 64 37
80 73 3H
90 82 46
100 91 4G
200 172 9B
300 253 E6
400 334 J1
500 415 12H
600 4A6 17C
700 587 1C7
800 668 1H2
900 749 20I
1000 82A 25D

View this as a standalone, printable table

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