The most common double letters in English are SS and LL. In our 106,000-word dictionary, SS appears in 5,116 words and LL in 4,546, followed by EE (1,892 words) and OO (1,816). Three doubles never occur at all: QQ, XX and YY.
These counts come from MyWordSolver’s own word database, built on the 1913 Webster’s Unabridged Dictionary. For each letter we counted how many entries contain that letter twice in a row. Below you’ll find the full table, what drives the big numbers, why some doubles are so rare, and what it all means for 5-letter word games.
How many words contain each double letter
Here is every double letter from AA to ZZ, ranked by the number of dictionary entries that contain it. The examples are familiar words that show each double in action.
| Rank | Double | Words containing it | Examples |
|---|---|---|---|
| 1 | SS | 5,116 | class, grass, success, kindness |
| 2 | LL | 4,546 | ball, hello, small, parallel |
| 3 | EE | 1,892 | green, sleep, coffee |
| 4 | OO | 1,816 | book, school, tooth |
| 5 | RR | 1,624 | carry, error, mirror |
| 6 | TT | 1,609 | letter, little, attack |
| 7 | NN | 1,088 | dinner, annual, tennis |
| 8 | PP | 1,056 | apple, happy, upper |
| 9 | MM | 1,038 | summer, hammer, common |
| 10 | FF | 964 | offer, staff, coffee |
| 11 | CC | 739 | accept, occur, success |
| 12 | GG | 587 | egg, giggle, struggle |
| 13 | DD | 523 | ladder, middle, address |
| 14 | BB | 485 | rabbit, ribbon, bubble |
| 15 | ZZ | 144 | puzzle, dizzy, buzz |
| 16 | II | 56 | Latin plurals such as radii and genii |
| 17 | AA | 54 | bazaar, aardvark |
| 18 | HH | 27 | withhold, fishhook |
| 19 | WW | 20 | powwow, glowworm |
| 20 | UU | 12 | vacuum, continuum |
| 21 | KK | 9 | bookkeeper, bookkeeping |
| 22 | VV | 6 | navvy, savvy |
| 23 | JJ | 1 | a single entry |
| 24 | 0 | none | |
| 25 | XX | 0 | none |
| 26 | YY | 0 | none |
Add up the middle column and you get 23,412. That isn’t the number of words with a double letter, because some words contain more than one kind: bookkeeper has three doubles in a row (OO, KK and EE) and is counted in all three rows.
The big four: SS, LL, EE and OO
SS and LL together account for 41% of all the double-letter counts in the table. Their lead comes mostly from word endings that English uses over and over:
- SS sits in the suffixes -ness (kindness, darkness), -less (careless, endless) and -ess (actress, princess), and in words ending -ssion (mission, passion). An unabridged dictionary is packed with -ness nouns, which is a big reason SS tops the table.
- LL turns up in short base words (all, ball, well, fill), in endings like -ally and -ically (basically, characteristically) and in hundreds of words built from them.
- EE and OO are the only two vowel doubles that spell everyday English sounds, as in see, moon and book. That’s why they reach the thousands while AA, II and UU stay in double digits.
Vowel doubles as a group (AA, EE, II, OO and UU) make up 3,830 of the counts, about 16% of the total. The rest are consonants.
The rare doubles
AA, II and UU: mostly borrowed
Because English doesn’t use AA, II or UU for any regular sound, words with them are usually borrowed. AA tends to come from other languages, as in bazaar and aardvark. II and UU mostly come from Latin, as in radii and vacuum. If you’re hunting for AA words specifically, our list of words with AA in the middle collects them.
HH, KK and WW: where two parts meet
These doubles rarely happen inside a single word part. They usually appear where two words or word parts are joined: with + hold, fish + hook, book + keeper, glow + worm. Powwow gets its WW from a repeated syllable.
VV and JJ: almost absent
Only six entries contain VV; familiar examples are informal words like navvy and savvy. JJ appears in exactly one entry. In modern word lists the usual JJ example is hajj, but for practical purposes JJ is a curiosity.
The doubles that never occur: QQ, XX and YY
Not one of the 106,000 entries in our dictionary contains QQ, XX or YY. There are good reasons for the first two:
- QQ: in English, Q is almost always followed by U, so it never gets the chance to double.
- XX: X already stands for two sounds (K + S), so spelling never needs to double it. Brand names don’t count.
- YY: Y usually ends a syllable or pairs with a vowel, and our dictionary has no entry where two Y’s sit side by side.
So if a puzzle ever seems to need a QQ, XX or YY, it’s time to rethink the answer.
Double letters in common 5-letter words
For Wordle and similar games, the full dictionary matters less than the everyday words. We checked the 472 five-letter words in our database that also appear on a list of the 3,000 most common English words. 52 of them (11.0%) contain a double letter, and only nine doubles appear at all:
| Double | Common 5-letter words | The words |
|---|---|---|
| EE | 11 | agree, cheek, green, sheet, sleep, speed, steel, sweep, sweet, three, wheel |
| SS | 10 | asset, class, cross, dress, essay, glass, grass, guess, issue, press |
| LL | 9 | allow, fully, hello, shall, shell, skill, small, smell, still |
| OO | 7 | blood, floor, loose, proof, shoot, tooth, troop |
| RR | 5 | carry, error, marry, sorry, worry |
| PP | 4 | apple, apply, happy, upper |
| FF | 3 | offer, staff, stuff |
| NN | 2 | funny, inner |
| CC | 1 | occur |
Two things stand out. First, TT is the sixth most common double in the full dictionary, yet no common 5-letter word on our list contains it, and the same goes for MM, GG, DD, BB and ZZ. Second, EE edges out SS among everyday 5-letter words, even though SS leads overall.
Where the double sits
Position matters too. Among those 52 common words, the double falls in the 3rd and 4th letters 22 times (green, happy, sorry), in the 4th and 5th letters 17 times (class, staff, three) and in the 2nd and 3rd letters 13 times (apple, error, offer). Not one common 5-letter word on our list starts with a double letter, although rarer ones do, such as EERIE.
To search by position, use our lists of 5-letter words whose 3rd and 4th letters are the same, 5-letter words ending with double letters and 5-letter words starting with double letters. For the whole set, see 5-letter words with double letters, and for the opposite, 5-letter words without double letters.
Tips for word games
- Don’t open with a double. A repeated letter wastes a slot on your first guess. Our ranking of the best Wordle starting words sticks to words with five different letters.
- Suspect a double when the letters run out. If you’ve found four letters and nothing fits, try doubling one of them, starting with E, S, L or O.
- Check the end of the word. Doubled S, L and F often sit at the end of short words: class, still, staff.
- Never bother with QQ, XX or YY. They don’t occur in our dictionary at all.
Doubles also explain a neat fact about palindromes: every palindrome with an even number of letters has a double letter in the middle, as in noon and deed. You’ll see it throughout our list of every palindrome in the dictionary.