English number words include numerals and various words derived from them, as well as a large number of words borrowed from other languages.

Cardinal numbers

Cardinal numbers refer to the size of a group. In English, these words are numerals.

0zero (nought)10ten 1one11eleven2two12 twelve 20twenty3three13thirteen 30thirty 4four14fourteen40forty5five15fifteen 50fifty6six16sixteen60sixty7seven17seventeen70seventy8eight18eighteen 80eighty 9nine19nineteen90ninety

If a number is in the range 21 to 99, and the second digit is not zero, the number is typically written as two words separated by a hyphen. 21twenty-one25twenty-five32thirty-two58fifty-eight64sixty-four79seventy-nine83eighty-three99ninety-nine

In English, the hundreds are perfectly regular, except that the word hundred remains in its singular form regardless of the number preceding it. 100one hundred 200two hundred......900nine hundred

So too are the thousands, with the number of thousands followed by the word "thousand". The number one thousand may be written 1 000 or 1000 or 1,000; larger numbers are written for example 10 000 or 10,000 for ease of reading. European languages that use the comma as a decimal separator may correspondingly use the period as a thousands separator. As a result, some style guides recommend avoidance of the comma (,) as either separator and the use of the period (.) only as a decimal point. Thus one-half would be written 0.5 in decimal, base ten notation, and fifty thousand as 50 000, and not 50.000 nor 50,000 nor 50000.

1,000one thousand2,000two thousand......10,000ten thousand or (rarely used) a myriad, which usually means an indefinitely large number.11,000eleven thousand......20,000twenty thousand21,000twenty-one thousand30,000thirty thousand85,000eighty-five thousand100,000one hundred thousand or one lakh (1,00,000) (Indian English)999,000nine hundred and ninety-nine thousand (inclusively British English, Irish English, Australian English, and New Zealand English)nine hundred ninety-nine thousand (American English)nine lac ninety-nine thousand (Indian English)1,000,000one million or ten lacs (10,00,000) (Indian English)10,000,000ten million or one crore (1,00,00,000) (Indian English)

In American usage four-digit numbers are often named using multiples of "hundred" and combined with tens and ones: "eleven hundred three", "twelve hundred twenty-five", "forty-seven hundred forty-two", or "ninety-nine hundred ninety-nine". In British usage, this style is common for multiples of 100 between 1,000 and 2,000 (e.g., 1,500 as "fifteen hundred") but not for higher numbers.

Many people pronounce four-digit numbers with non-zero tens and ones as pairs of two-digit numbers without saying "hundred" and inserting "oh" for zero tens: "twenty-six fifty-nine" or "forty-one oh five". This usage probably evolved from the distinctive usage for years; "nineteen-eighty-one", or from four-digit numbers used in the American telephone numbering system which were originally two letters followed by a number followed by a four-digit number, later by a three-digit number followed by the four-digit number. It is avoided for numbers less than 2500 if the context may mean confusion with time of day: "ten ten" or "twelve oh four".

Intermediate numbers are read differently depending on their use. Their typical naming occurs when the numbers are used for counting. Another way is for when they are used as labels. The second column method is used much more often in American English than British English. The third column is used in British English but rarely in American English (although the use of the second and third columns is not necessarily directly interchangeable between the two regional variants). In other words, British English and American English can seemingly agree, but it depends on a specific situation (in this example, bus numbers).

Common British vernacularCommon American vernacularCommon British vernacular"How many marbles do you have?""What is your house number?""Which bus goes to the High Street?"101"A hundred and one.""One-oh-one."Here, "oh" is used for the digit zero."One-oh-one."109"A hundred and nine.""One-oh-nine.""One-oh-nine."110"A hundred and ten.""One-ten.""One-one-oh."117"A hundred and seventeen.""One-seventeen.""One-one-seven."120"A hundred and twenty.""One-twenty.""One-two-oh", "One-two-zero."152"A hundred and fifty-two.""One-fifty-two.""One-five-two."208"Two hundred and eight.""Two-oh-eight.""Two-oh-eight."394"Three hundred and ninety-four.""Three-ninety-four.""Three-ninety-four." or "Three-nine-four." Note: When a cheque (or check) is written, the number 100 is always written "one hundred". It is never "a hundred".

In American English, many students are taught not to use the word and anywhere in the whole part of a number, so it is not used before the tens and ones. It is instead used as a verbal delimiter when dealing with compound numbers. Thus, instead of "three hundred and seventy-three", "three hundred seventy-three" would be said. Despite this rule, some Americans use the and in reading numbers containing tens and ones as an alternative.

Very large numbers For numbers above a million, there are three main systems used to form numbers in English. (For the use of prefixes such as kilo- for a thousand, mega- for a million, milli- for a thousandth, etc. see SI units.) These are: the long scale – designates a system of numeric names formerly used in British English, but now obsolete, in which a billion is used for a million million (and similarly, with trillion, quadrillion etc., the prefix denoting the power of a million); and a thousand million is sometimes called a milliard. This system is still used in several other European languages. There is some favour for this scale in astronomy, due to the issue of the vastness of the Universe. the short scale – always used in American English and almost always in British English since the politically ordained formal adoption of this scale in the 1970s – designates a system of numeric names in which a thousand million is called a billion, and the word milliard is not used. the Indian numbering system, used widely across Indian subcontinent.

Many people have no direct experience of manipulating numbers this large, and many non-American readers may interpret billion as 1012 (even if they are young enough to have been taught otherwise at school); moreover, usage of the "long" billion is standard in some non-English-speaking countries. For these reasons, defining the word may be advisable when writing for the public.

Number notationPowernotationShort scaleLong scaleIndian(or South Asian) English1,000,000106one millionone millionten lakh1,000,000,000109one billiona thousand millionone milliarda thousand millionone hundred crore(one arab)1,000,000,000,0001012one trilliona thousand billionone billiona million millionone lakh crore(ten kharab)1,000,000,000,000,0001015one quadrilliona thousand trillionone billiarda thousand billionten crore crore(one padma)1,000,000,000,000,000,0001018one quintilliona thousand quadrillionone trilliona million billionten thousand crore crore(ten shankh)1,000,000,000,000,000,000,0001021one sextilliona thousand quintillionone trilliarda thousand trillionone crore crore crore(one ankh)

The numbers past one trillion in the short scale, in ascending powers of 1000, are as follows: quadrillion, quintillion, sextillion, septillion, octillion, nonillion, decillion, undecillion, duodecillion, tredecillion, quattuordecillion, quindecillion, sexdecillion, septendecillion, octodecillion, novemdecillion and vigintillion (which is 10 to the 63rd power, or a one followed by 63 zeros). The highest number in this series listed in modern dictionaries is centillion, which is 10 to the 303rd power.Webster's Third New International Dictionary, Unabridged, 1993, Merriam-Webster The interim powers of one thousand between vigintillion and centillion do not have standardized names, nor do any higher powers, but there are many extensions in use. The highest number listed in Robert Munafo's table of such unofficial names is milli-millillion, which was coined as a name for 10 to the 3,000,003rd power.

The googolplex was often cited as the largest named number in English. If a googol is ten to the one hundredth power, then a googolplex is one followed by a googol of zeros (that is, ten to the power of a googol). There is the coinage, of very little use, of ten to the googolplex power, of the word googolplexplex.

The terms arab, kharab, padma and shankh are more commonly found in old books on Indian mathematics.

Here are some approximate composite large numbers in American English: QuantityWrittenPronounced1,200,0001.2 millionone point two million3,000,0003 millionthree million250,000,000250 milliontwo hundred fifty million6,400,000,0006.4 billionsix-point four billion23,380,000,00023.38 billiontwenty-three-point three eight billion

Often, large numbers are written with (preferably non-breaking) half-spaces or thin spaces separating the thousands (and, sometimes, with normal spaces or apostrophes) instead of commas—to ensure that confusion is not caused in countries where a decimal comma is used. Thus, a million is often written 1 000 000. In some areas, a point (. or ·) may also be used as a thousands separator, but then the decimal separator must be a comma (,). In English the point (.) is used as the decimal separator, and the comma (,) as the thousands separator.

Special names

Some numbers have special names in addition to their regular names, most depending on context.

0: zero: formal scientific usage nought: mostly British usage, common in science to refer to subscript 0 indicating an initial state naught: archaic term for nothingness, which may or may not be equivalent to the number; mostly American usage, old-fashioned spelling of nought aught: proscribed but still occasionally used when a digit is 0 (as in "thirty-aught-six", the .30-06 Springfield rifle cartridge and by association guns that fire it). Aughts can also refer to the first decade of this century in American English, though it may not be universally understood. oh: used when spelling numbers (like telephone, bank account, bus line [British: bus route]) but can cause confusion with the letter o if reading a mix of numbers and letters nil: in general sport scores, British usage ("The score is two–nil.") nothing: in general sport scores, American usage ("The score is two–nothing.") null: to an object or idea related to nothingness. The 0th aleph number () is pronounced "aleph-null". love: in tennis, badminton, squash and similar sports (origin disputed, said by the Oxford English Dictionary to be from the idea that when one does a thing "for love", that is for no monetary gain, the word "love" implies "nothing". The previously held belief that it originated from , due to its shape, is no longer widely accepted) zilch, (from Spanish), zip: used informally when stressing nothingness; this is true especially in combination with one another ("You know nothing—zero, zip, , zilch!"); American usage nix: also used as a verb; mostly American usage cypher / cipher: archaic, from French , in turn from Arabic , meaning zero goose egg (informal) duck (used in cricket when a batsman is dismissed without scoring) blank the half of a domino tile with no pips 1: ace in certain sports and games, as in tennis or golf, indicating success with one stroke, and the face of a die, playing card or domino half with one pip birdie in golf denotes one stroke less than par, and bogey, one stroke more than par solo unit linear the degree of a polynomial is 1; also for explicitly denoting the first power of a unit: linear metre unity in mathematics protagonist first actor in theatre of Ancient Greece, similarly Proto-Isaiah and proton 2: couple brace, from Old French "arms" (the plural of arm), as in "what can be held in two arms". pair