Random letter generator
One letter or a row of them, from the whole alphabet, the vowels or the consonants, each with the same chance.
How many letters are in each set
| Set | Letters | Count | Chance of each |
|---|---|---|---|
| All letters | A to Z | 26 | 1 in 26 (3.85%) |
| Vowels | A, E, I, O, U | 5 | 1 in 5 (20%) |
| Consonants | The other 21, including W and Y | 21 | 1 in 21 (4.76%) |
| All letters, mixed case | A to Z and a to z | 52 | 1 in 52 (1.92%) |
Each letter is drawn with your browser’s cryptographic random generator, which picks a position in the set with no modulo bias. Letters you leave out are removed first, so the set gets smaller and every remaining letter keeps an equal share. With “No repeats”, letters are drawn one at a time from those still left, like tiles from a bag.
Uses for random letters
| Use | Settings |
|---|---|
| A starting letter for Scattergories-style word games or “name a country beginning with…” | One letter; leave out Q, X and Z if those letters stall the game |
| A letter-tile rack for practising anagrams | 7 letters, repeats allowed, or 2 vowels and 5 consonants drawn separately |
| Phonics and alphabet practice in class | One small letter at a time, or 26 with no repeats to work through the alphabet |
| Picking a group or seat row labelled A to F | One letter, leave out G to Z |
| Initials or placeholder names for characters, test data or brainstorming | 2 or 3 capitals |
| A random order for 26 lettered items | 26 letters, no repeats |
For a word game that mimics real English, a uniform draw gives far more awkward letters than a bag of tiles would. The next section shows the size of the difference.
English letter frequency compared with a random pick
In English text the letters are very unevenly used. Peter Norvig counted the letters in the Google Books English word data, about 3.56 million million letters in all, and found E made up 12.49% of them and Z 0.09%. A uniform random pick gives each letter 1 in 26, or 3.85%, so E appears about a third as often from this generator as it does in writing, and Z about 43 times as often.
| Letter | Share of English text | Compared with 3.85% |
|---|---|---|
| E | 12.49% | 3.2× |
| T | 9.28% | 2.4× |
| A | 8.04% | 2.1× |
| O | 7.64% | 2.0× |
| I | 7.57% | 2.0× |
| N | 7.23% | 1.9× |
| S | 6.51% | 1.7× |
| R | 6.28% | 1.6× |
| H | 5.05% | 1.3× |
| L | 4.07% | 1.1× |
| D | 3.82% | 1.0× |
| C | 3.34% | 0.9× |
| U | 2.73% | 0.7× |
| M | 2.51% | 0.7× |
| F | 2.40% | 0.6× |
| P | 2.14% | 0.6× |
| G | 1.87% | 0.5× |
| W | 1.68% | 0.4× |
| Y | 1.66% | 0.4× |
| B | 1.48% | 0.4× |
| V | 1.05% | 0.3× |
| K | 0.54% | 0.1× |
| X | 0.23% | 0.06× |
| J | 0.16% | 0.04× |
| Q | 0.12% | 0.03× |
| Z | 0.09% | 0.02× |
Source: Peter Norvig, English Letter Frequency Counts: Mayzner Revisited, from the Google Books Ngram data (English, version 20120701). The five vowels make up 38.47% of letters in that count, twice the 19.2% (5 in 26) that a uniform pick gives them, so random rows look short of vowels. Drawing vowels and consonants separately is the simple fix.
Repeats, and how often they happen
With repeats allowed, each letter is drawn from the full set, so the chance of at least one repeat grows quickly, as in the birthday problem. For k letters from a set of N, the chance that all are different is N × (N − 1) × … × (N − k + 1) ÷ Nk.
| Letters drawn | From A–Z (26) | Consonants (21) | Vowels (5) |
|---|---|---|---|
| 2 | 3.8% | 4.8% | 20.0% |
| 3 | 11.2% | 13.8% | 52.0% |
| 4 | 21.5% | 26.1% | 80.8% |
| 5 | 33.6% | 40.2% | 96.2% |
| 7 | 58.7% | 67.5% | 100% |
| 10 | 86.3% | 92.3% | 100% |
Six or more vowels must include a repeat, since there are only five. Tick “No repeats” for different letters every time; the generator then refuses to draw more letters than the set holds.
Questions
Is Y a vowel or a consonant here?
A consonant. The vowel set is A, E, I, O and U, the five letters usually taught as vowels, and the consonant set is the other 21 letters, including Y and W. If you want Y among the vowels, choose all letters and leave out the consonants you don’t want, or draw consonants and leave out Y.
Why do I keep getting letters like Q, X and Z?
Because every letter has the same 1 in 26 chance, unlike in English text, where Z makes up less than a tenth of one per cent of letters. Five random letters include at least one of J, Q, X or Z more often than not (56.6% of the time), while in English text those four make up 0.6% of letters.
How does “Both, mixed” case work?
Each letter is chosen first, with a 1 in 26 chance for each, and then made a capital or a small letter with an even chance. “No repeats” applies to the letter, so with mixed case you won’t get both A and a in one draw.
Can I get every letter of the alphabet in a random order?
Yes. Ask for 26 letters with “No repeats” ticked, or use the “Whole alphabet shuffled” link. Each of the 403,291,461,126,605,635,584,000,000 possible orders (26 factorial) is equally likely.
How do I leave out letters?
Type them in the “Leave out” box in any case, with or without spaces or commas, such as Q X Z. They are removed before the draw, so the letters that remain share the chance equally; leaving out Q, X and Z gives each of the other 23 letters a 1 in 23 chance.