Indian numbering system
The Indian numbering system is used in India, Pakistan, Nepal, Sri Lanka, and Bangladesh to express large numbers, which differs from the International System of Units. Commonly used quantities include lakh and crore written as 1,00,000 and 1,00,00,000 respectively in some locales. For example: 150,000 rupees is "1.5 lakh rupees" which can be written as "1,50,000 rupees", and 30,000,000 rupees is referred to as "3 crore rupees" which can be written as "3,00,00,000 rupees".
There are names for numbers larger than crore, but they are less commonly used. These include arab, kharab, nil or sometimes transliterated as neel, padma, shankh, and mahashankh. In common parlance, the lakh and crore terminology repeats for larger numbers. Thus lakh crore is 1012.
In the ancient Indian system, still in use in regional languages of India, there are words for. These names respectively starting at 1000 are sahasra, ayuta, laksha, niyuta, koti, arbhudha, abhja, karva, nikarva, mahapadma, shanmkhu, jaladhi, amtya, madhya, paraardha. In the Indian system, now prevalent in the northern parts, the next powers of ten are one lakh, ten lakh, one crore, ten crore, one arab, and so on.
Multiples
The Indian system is decimal, same as in the International System of Units, and the first five orders of magnitude are named in a similar way: one, ten, one hundred, one thousand, and ten thousand. For higher powers of ten, naming diverges. The Indian system uses names for every second power of ten: lakh, crore, arab, kharab, etc. In the long and short scales, there are names for every third power of ten. The short scale uses million, billion, trillion, etc.Decimal formatting
The Indian system groups digits of a large decimal is represented differently than the International System of Units. The Indian system does group the first three digits to the left of the decimal point, but thereafter, groups by two digits to align with the naming of quantities at multiples of 100.| Indian | English |
| 5,00,000 | 500,000 |
| 12,34,56,789 | 123,456,789 |
| 17,00,00,00,000 | 17,000,000,000 |
| 6,78,90,00,00,00,00,000 | 6,789,000,000,000,000 |
Like English and other locales, the Indian system uses a period as the decimal separator and the comma for grouping, while others use a comma for decimal separator and a thin space or point to group digits.
Pronunciation in English
When speakers of indigenous Indian languages are speaking English, the pronunciations may be closer to their mother tongue.- lakh /lɑːkʰ/
- crore /kɹɔːɹ/
- arab /ʌˈɾʌb/
- kharab /kʰʌˈɾʌb/
Names of numbers
Historic numbering systems
Numbering systems in Hindu epics
There are various systems of numeration found in various ancient epic literature of India. The following table gives one such system used in the Valmiki Ramayana.| Name | Indian decimal | Value | Short scale |
| एक | 1 | 1 | one |
| दश | 10 | 10 | ten |
| शत | 100 | 102 | hundred |
| सहस्र | 1,000 | 103 | thousand |
| लक्ष | 1,00,000 | 105 | hundred thousand |
| कोटि | 1,00,00,000 | 107 | ten million |
| शङ्कु | 1,00,000 | 1012 | trillion |
| महाशङ्कु | 1,00,000 | 1017 | hundred quadrillion |
| वृन्द | 1,00,000 | 1022 | ten sextillion |
| महावृन्द | 1,00,000 | 1027 | octillion |
| पद्म | 1,00,000 | 1032 | hundred nonillion |
| महापद्म | 1,00,000 | 1037 | ten undecillion |
| खर्व | 1,00,000 | 1042 | tredecillion |
| महाखर्व | 1,00,000 | 1047 | hundred quattuordecillion |
| समुद्र | 1,00,000 | 1052 | ten sexdecillion |
| ओघ | 1,00,000 | 1057 | octodecillion |
| महौघ | 1,00,000 | 1062 | hundred novemdecillion |
Other numbering systems
The denominations by which land was measured in the Kumaon Kingdom were based on arable lands and thus followed an approximate system with local variations. The most common of these was a vigesimal numbering system with the main denomination called a bisi, which corresponded to the land required to sow 20 nalis of seed. Consequently, its actual land measure varied based on the quality of the soil. This system became the established norm in Kumaon by 1891.Usage in different languages
Below is a list of translations for the words lakh and crore in other languages spoken in the Indian subcontinent:Formal written publications in English in India tend to use lakh/crore for Indian currency and International numbering for foreign currencies.
Current usage
The official usage of this system is limited to the nations of India, Pakistan and Bangladesh. It is universally employed within these countries, and is preferred to the International numbering system.Sri Lanka and Nepal used this system in the past but has switched to the International numbering system in recent years. In the Maldives, the term lakh is widely used in official documents and local speech. However, the International System of Units is preferred for higher denominations.
Most institutions and citizens in India use the Indian number system. The Reserve Bank of India was noted as a rare exception in 2015, whereas by 2024 the Indian system was used for amounts in rupees and the International system for foreign currencies throughout the Reserve Bank's website.