Large Number Name Converter｜What Is This Number Called and How Many Digits Does It Have?
A calculator shows 1e26. A report quotes a figure with a long tail of zeros. Counting those zeros by eye is slow and easy to get wrong. Paste the number here and the page names it: 1e26 is 100 septillion, a 27-digit number.
💡 What This Tool Shows
Paste a number and the page lays out several views of it together.
- Name (short scale): the number split into groups of three digits with thousand, million, billion and so on. A 24-digit number such as 602214076000000000000000 reads "602 sextillion 214 quintillion 76 quadrillion".
- Digit ruler: every group of three digits in its own box with its name underneath. The highest group is highlighted, so you can see where the name comes from.
- Long scale name: the same number with milliard, billion, billiard and the rest of the long-scale series.
- Digit count and separators: how many digits the whole-number part has, and the number written with commas.
- Scientific notation: both the 6.02 × 10^23 form and the 6.02e+23 form.
- SI prefix: from one thousand up to just under 10^33, the value written with a prefix symbol such as k, M or G.
Accepted input includes plain digits, digits with commas or spaces, 1e26, 6.02×10^23 and 10^20. Names are given for whole-number parts of up to 72 digits. Short-scale names run from thousand to vigintillion (10^63); for anything from 10^66 upward the page says there is no common name and still gives the digit count and notation.
🧐 FAQ
What comes after a trillion?
Quadrillion (10^15), then quintillion (10^18), sextillion (10^21), septillion (10^24), octillion (10^27), nonillion (10^30) and decillion (10^33). Each step is a thousand times the one before. The series this page uses continues through undecillion, duodecillion and onward to vigintillion at 10^63.
How do I read 1e26?
The "e" means "times ten to the power of". 1e26 is a 1 followed by 26 zeros, which makes 27 digits, and its short-scale name is 100 septillion. In the long scale the same number is 100 quadrillion.
Is a billion a thousand million or a million million?
It depends on the scale. In the short scale, a billion is a thousand million (10^9). In the long scale, a billion is a million million (10^12), and 10^9 is a milliard or simply "a thousand million". American English used the short scale, and British English traditionally used the long one. After decades of growing informal use of the short scale in Britain, the UK government adopted it in 1974, and that is the meaning in official British use. Older British texts may still mean a million million, which is why the page shows both names.
Why does the long-scale row use words like "trilliard"?
Long-scale names move up by a factor of a million: million, billion (10^12), trillion (10^18). The steps in between take the ending "-iard": milliard (10^9), billiard (10^15), trilliard (10^21). These forms are standard in French. Treat that row as a reading aid for translated or older material.
What happens with decimals or negative numbers?
Only the whole-number part is named. If the number has a fraction, a notice under the input says so, and the scientific notation rows keep the full value. A leading minus sign is kept as the word "minus".
📚 Background: Two Scales, One Set of Words
Both scales use the same Latin-based words but assign them differently. The long scale goes back to the French mathematician Nicolas Chuquet, whose 1484 manuscript described naming numbers in groups of six digits. In that system each new word is a million times the last one. The short scale moves to a new word every three digits instead, so its billion arrives at 10^9.
The result is that "billion" is a false friend between languages. An English billion is a thousand million, while the similar-looking word in Spanish or French means a million million. Translators and anyone comparing figures across languages need to check which scale a source uses.
For measurements, the SI prefixes avoid the problem because they are tied to powers of ten and not to number words. The prefix list published by the BIPM goes up to quetta, which stands for 10^30, with ronna for 10^27 just below it.