Number to Words
Spell out any number in English words, including a cheque-writing format with the cents as a fraction, and handle the British and American differences.
You can count to 999 without using the letter A — if you are American
The old puzzle is that no number name below a thousand contains the letter A, and that one thousand is the first one that does. Checking every name from zero to 999 confirms it: not one of them contains an A.
Except that it depends on where you live, which is the more interesting half. British usage puts an "and" before the last part of a hundred, so 101 is one hundred and one rather than one hundred one, and the first A arrives at 101 instead of 1,000. The puzzle has two correct answers. That same choice is one any converter has to make and few state — this one uses the American form, which is the convention for cheques.
Written out, the other letters are far more lopsided than the A is famous for being:
| Letter | First appears in | Which is |
|---|---|---|
| d | one hundred | 100 |
| a | one thousand | 1,000 |
| b | one billion | 10^9 |
| c | one octillion | 10^27 |
D turns up almost immediately, in "hundred". B has to wait for "billion" at 109. C waits longest of all — the first number name containing a C is one octillion, which is 1027, and you will not reach it by counting. And two letters never appear at all: J AND K are in no English number name anywhere up to a decillion.
Every number is four letters away from four
Take any number, write it out, count the letters, and write that out. Repeat. You always arrive at 4, and then you stop, because "four" has four letters. Starting from 323:
| Number | Written out | Letters |
|---|---|---|
| 323 | three hundred twenty-three | 23 |
| 23 | twenty-three | 11 |
| 11 | eleven | 6 |
| 6 | six | 3 |
| 3 | three | 5 |
| 5 | five | 4 |
| 4 | four | 4 |
That is the longest route there is below a hundred thousand — 6 steps. Every number from 0 to 100,000 was tried and every one of them lands on four, with no exceptions and nothing that cycles.
The reason it cannot end anywhere else is worth stating, because it makes the trick stop being a trick. A chain can only stop at a number whose name is exactly as long as the number itself, and searching every value to 100,000 finds precisely one: 4. Nothing else is a fixed point, so there is nowhere else to stop. It also survives the dialect change — the British names are different but they converge on four just the same.
How to use
- Enter a number, with decimals if needed.
- Read the spelled-out form.
- Switch to cheque format for writing payments.
- Pick British or American style for the word 'and'.
Frequently asked questions
Why do cheques need the amount in words?
Because words are far harder to alter than digits. Adding a zero to a figure takes a moment; changing 'one hundred' to 'one thousand' convincingly does not. Where the words and figures disagree, the words normally govern.
What is the correct cheque format for cents?
The dollars in words, then the cents as a fraction over 100 — for example, one hundred and forty-two dollars and 56/100. Writing the cents as a fraction rather than words is the long-standing convention, and a line drawn to the end of the field prevents anything being added.
Do the British and Americans differ?
Yes, over the word 'and'. British usage writes one hundred and forty-two; American usage more often writes one hundred forty-two. Both are perfectly understood, and the difference matters mainly for consistency within a document.
When are the hyphens used?
In compound numbers from twenty-one to ninety-nine. So it is forty-two and sixty-seven, but two hundred and one thousand take no hyphen. This is one of the more consistently applied rules in English spelling.
What comes after a billion?
Trillion, quadrillion, quintillion. There is a historical trap here: a billion once meant a million million in British usage, against a thousand million in American. Britain adopted the American meaning officially in 1974, but older documents may use the other, and the difference is a factor of a thousand.
How do I write a number with decimals?
For money, as dollars and cents. For a general quantity, read the decimal point as 'point' followed by the digits individually — 3.14 is three point one four, not three point fourteen. Reading them as a pair is a common error that changes the value implied.
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