This article may not meet the general notability guideline. Please help to establish notability by adding reliable, secondary sources about the topic. If notability cannot be established, the article is likely to be merged, redirected, or deleted. (October 2009)

Numeral systems by culture
Hindu-Arabic numerals
Eastern Arabic Indian family Khmer	Mongolian Thai Western Arabic
East Asian numerals
Chinese Counting rods Japanese	Korean Suzhou
Alphabetic numerals
Abjad Armenian Āryabhaṭa Cyrillic	Ge'ez Greek (Ionian) Hebrew
Other systems
Attic Babylonian Brahmi Egyptian Etruscan Inuit	Mayan Quipu Roman Urnfield
List of numeral system topics
Positional systems by base
Decimal (10)
1, 2, 3, 4, 5, 8, 12, 16, 20, 60, more…
v • d • e

Base 30 or trigesimal is a positional numeral system using 30 as the radix. Digits in this base can be represented using the Arabic numerals 0-9 and the Latin letters A-T.

From a mathematical viewpoint, 30 is a convenient choice for a base in that it is divisible by the three smallest prime numbers (2, 3, and 5) and by their multiples 6, 10, and 15 — many vulgar fractions are easily expressed in base 30. On the other hand, base 30 has poor radix economy, and it shares the problem with base 60 of its radix falling between twin primes, resulting in few recurring fractions having short periods.

Conversion table

Decimal	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14
Base 30	0	1	2	3	4	5	6	7	8	9	A	B	C	D	E
Decimal	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29
Base 30	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T

Decimal base Prime factors of the base: 2, 5			Base 30 Prime factors of the base: 2, 3, 5
Fraction	Prime factors of the denominator	Positional representation	Positional representation	Prime factors of the denominator	Fraction
1/2	2	0.5	0.F	2	1/2
1/3	3	0.3333... = 0.3	0.A	3	1/3
1/4	2	0.25	0.7F	2	1/4
1/5	5	0.2	0.6	5	1/5
1/6	2, 3	0.16	0.5	2, 3	1/6
1/7	7	0.142857	0.48H	7	1/7
1/8	2	0.125	0.3MF	2	1/8
1/9	3	0.1	0.3A	3	1/9
1/10	2, 5	0.1	0.3	2, 5	1/A
1/11	11	0.09	0.2LOGAR85DJ	B	1/B
1/12	2, 3	0.083	0.2F	2, 3	1/C
1/13	13	0.076923	0.296RKN	D	1/D
1/14	2, 7	0.0714285	0.248H	2, 7	1/E
1/15	3, 5	0.06	0.2	3, 5	1/F
1/16	2	0.0625	0.1Q7F	2	1/G
1/17	17	0.0588235294117647	0.1MS7	H	1/H
1/18	2, 3	0.05	0.1K	2, 3	1/I
1/19	19	0.052631578947368421	0.1HB	J	1/J
1/20	2, 5	0.05	0.1F	2, 5	1/K
1/21	3, 7	0.047619	0.1CPL	3, 7	1/L
1/22	2, 11	0.045	0.1AR85DJ2LOG	2, B	1/M
1/23	23	0.0434782608695652173913	0.193RBM56FJGSKQ2I7ONEAD	N	1/N
1/24	2, 3	0.0416	0.17F	2, 3	1/O
1/25	5	0.04	0.16	5	1/P
1/26	2, 13	0.0384615	0.14IDPBG	2, D	1/Q
1/27	3	0.037	0.13A	3	1/R
1/28	2, 7	0.03571428	0.1248H	2, 7	1/S
1/29	29	0.0344827586206896551724137931	0.1	T	1/T
1/30	2, 3, 5	0.03	0.1	2, 3, 5	1/10

This number article is a stub. You can help Wikipedia by expanding it. v • d • e