Numbers are the basic of Mathematics. Strange that Hindi numbers are unorganized unlike Sanskrit and other Southern Indian languages. Like other Sanskrit derived/Indian languages, Hindi numbers also follow decimal format.
Hindi cardinal numbers up to 100 have no specific standardization. Up to 20, the numbers are unique. After that each tenth number (such as 30, 40 etc) is unique. The rest of the numbers take the form of prefix of incremental digit and the base of preceding tenth number. However these prefixes and bases vary slightly and in a random manner. Although the pattern isn't regular, don't worry too much. They're just slightly different and with some practice you'd soon get the hang of it. Here are the numbers from 21 to 100. Try to follow them and find any similar pattern.
Numeral
English
Hindi
Transliteration
21
Twenty one
इक्कीस
ikkīs
22
Twenty two
बाईस
bāīs
23
Twenty three
तेईस
tēīs
24
Twenty four
चौबिस
chaubīs
25
Twenty five
पच्चीस
pachchīs
26
Twenty six
छब्बीस
chhabbīs
27
Twenty seven
सत्ताईस
sattāīs
28
Twenty eight
अट्ठाईस
aṭṭhāīs
29
Twenty nine
उनतीस
untīs
30
Thirty
तीस
tīs
31
Thirty one
इकतीस
iktīs
32
Thirty two
बत्तीस
battīs
33
Thirty three
तैंतीस
taiṃtīs
34
Thirty four
चौंतीस
chauṃtīs
35
Thirty five
पैंतीस
paiṃtīs
36
Thirty six
छत्तीस
chattīs
37
Thirty seven
सैंतीस
saiṃtīs
38
Thirty eight
अड़तीस
aṛtīs
39
Thirty nine
उनतालीस
untālīs
40
Forty
चालीस
chālīs
Numeral
English
Hindi
Transliteration
41
Forty one
इकतालीस
iktālīs
42
Forty two
बयालीस
bayālīs
43
Forty three
तैंतालीस
taiṃtālīs
44
Forty four
चौंतालीस
chauṃtālīs
45
Forty five
पैंतालीस
paiṃtālīs
46
Forty six
छियालीस
chhiyālīs
47
Forty seven
सैंतालीस
saiṃtālīs
48
Forty eight
अड़तालीस
aṛtālīs
49
Forty nine
उनचास
unchās
50
Fifty
पचास
pachās
51
Fifty one
इक्यावन
ikyāvan
52
Fifty two
बावन
bāvan
53
Fifty three
तिरपन
tirpan
54
Fifty four
चौवन
chauvan
55
Fifty five
पचपन
pachpan
56
Fifty six
छप्पन
chhappan
57
Fifty seven
सत्तावन
sattāvan
58
Fifty eight
अट्ठावन
aṭṭhāvan
59
Fifty nine
उनसठ
unsaṭh
60
Sixty
साठ
sāṭh
Numeral
English
Hindi
Transliteration
61
Sixty one
इकसठ
iksaṭh
62
Sixty two
बासठ
bāsaṭh
63
Sixty three
तिरसठ
tirsaṭh
64
Sixty four
चौंसठ
chauṃsaṭh
65
Sixty five
पैंसठ
paiṃsaṭh
66
Sixty six
छयासठ
chhiyāsaṭh
67
Sixty seven
सड़सठ
saṛsaṭh
68
Sixty eight
अड़सठ
aṛsaṭh
69
Sixty nine
उनहत्तर
unhattar
70
Seventy
सत्तर
sattar
71
Seventy one
इकहत्तर
ik'hattar
72
Seventy two
बहत्तर
bahattar
73
Seventy three
तिहत्तर
tihattar
74
Seventy four
चौहत्तर
chauhattar
75
Seventy five
पचहत्तर
pach'hattar
76
Seventy six
छिहत्तर
chhihattar
77
Seventy seven
सतहत्तर
sat'hattar
78
Seventy eight
अठहत्तर
aṭhhattar
79
Seventy nine
उनासी
unāsī
80
Eighty
अस्सी
assī
Numeral
English
Hindi
Transliteration
81
Eighty one
इक्यासी
ikyāsī
82
Eighty two
बयासी
bayāsī
83
Eighty three
तिरासी
tirāsī
84
Eighty four
चौरासी
chaurāsī
85
Eighty five
पचासी
pachāsī
86
Eighty six
छियासी
chhiyāsī
87
Eighty seven
सत्तासी
sattāsī
88
Eighty eight
अठासी
aṭhāsī
89
Eighty nine
नवासी
navāsī
90
Ninety
नब्बे
nabbē
91
Ninety one
इक्यानवे
ikyānavē
92
Ninety two
बानवे
bānavē
93
Ninety three
तिरानवे
tirānavē
94
Ninety four
चौरानवे
chaurānavē
95
Ninety five
पचानवे
pachānavē
96
Ninety six
छियानवे
chhiyānavē
97
Ninety seven
सत्तानवे
sattānavē
98
Ninety eight
अट्ठानवे
aṭṭhānavē
99
Ninety nine
निन्यानवे
ninyānavē
100
(One) hundred
(एक) सौ
(ēk) sau
Once you have got through the numbers 1-100 the rest of the numbers are regular.
Another point to be noted in Hindi in case of cardinal numbers is that Hindi (and all other Indic languages) often use quantities like lakh and crore which are less common in English speaking countries. The opposite is true for quantities like million, billion (We are talking about the US billion which is 1 followed by 9 zeros, not the UK billion which is 1 followed by 12 zeros.), trillion etc.
Hindi ordinals are a piece of cake once you are thorough with the cardinals. Only the first six ordinals are unique.[1]
English
Hindi
Transliteration
First (1st)
पहला/प्रथम (१ला/१म)
pahalā/prathama
Second (2nd)
दूसरा/द्वितीय (२रा/२य)
dusarā/dvitīya
Third (3rd)
तीसरा/तृतीय (३रा/३य)
tisarā/tr̥tīya
Fourth (4th)
चौथा/चतुर्थ (४था/४र्थ)
chauthā/chaturtha
Fifth (5th)
पांचवां/पंचम (५वां/५म)
pāṃcavāṃ/paṃcama
Sixth (6th)
छठा/षष्ठ (६ठा/६ष्ठ)
chaṭhā/ṣaṣṭha
Seventh (7th)
सातवां/सप्तम (७वां/७म)
sātavāṃ/saptama
Eighth (8th)
आठवां/अष्टम (८वां/८म)
āṭhavāṃ/aṣṭama
Ninth (9th)
नौवां/नवम (९वां/९म)
nauvāṃ/navama
Tenth (10th)
दशवां/दशम (१०वां/१०म)
daśavāṃ/daśama
As you would have noticed by now that in Hindi 'वां' acts just like 'th' in English which you can add to the end of cardinal numbers to form the corresponding ordinal numbers. If you're wondering about the irregularities of the second options, then let us just tell you that they are the Sanskrit ordinal numbers that are used often in Hindi. You just have to remember ten of them (for they sometimes appear in texts/speeches). After ten, any ordinal numbers you would encounter would be most likely in the general form of ordinal number+vāṃ
