Phoneme Frequency Tables

Phoneme Frequency Tables

We've identified two ways to rank the possible spelling of any given phoneme for our data set of over 26,000 words. In the first, we count the number of times a phoneme-grapheme correspondence occurs in the list of words. In the second, we give a weight to each word in the list depending on its frequency in connected text, then multiply each correspodence by that weight.

Why Adding a Frequency Weight Matters

Let's consider the sound /v/, which can be represented by the letter 'v' or the letter 'f'. In our data, there are about 1,700 words that use 'v' and only one word ('of') that uses 'f' (technically two words use this, thereof, being the other). Let's look at an excerpt from "Wizard of Oz" by L. Frank Baum to see why this matters.

When Dorothy stood in the doorway and looked around, she could see nothing but the great gray prairie on every side. Not a tree nor a house broke the broad sweep of flat country that reached to the edge of the sky in all directions. The sun had baked the plowed land into a gray mass, with little cracks running through it. Even the grass was not green, for the sun had burned the tops of the long blades until they were the same gray color to be seen everywhere.

As we can see above, the word 'of' occurs as often as all the other words that include the letter 'v'. It is one of the most common words in English!

So, if you're reading connected text and come across a spelling of the sound /v/, it's just as likely to be spelled with the letter 'f' as it is with the letter 'v'. This is a rather extreme example. Many of the other sounds have similar results regardless of how we rank them, but we can use this data to inform our teaching approaches.

Below you can see the breakdown of each correspondence for the sound /v/. We have a table for the direct frequencies and one for the weighted frequencies.

Grapheme Frequency (total) Frequency (%)
v 1,724 82.73
ve 356 17.08
f 2 0.10
vv 2 0.10
Grapheme Weighted Frequency (total) Weighted Frequency (%)
f 4,137,188.65 43.92
v 3,412,584.87 36.22
ve 1,870,421.10 19.86
vv 111.77 0.00

Frequency Tables by Phoneme

We've run rankings for our entire data set. Below you can find the frequency and weighted frequency for the spellings of each phoneme. You can click on each grapheme to see the words with that correspondence in our Word List Builder.

See our Methodology at the bottom for more details.

Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
a
4,002 99.43 15,920,476.63 98.48
eah
1 0.02 140,297.71 0.87
au
7 0.17 50,817.53 0.31
al
6 0.15 48,540.10 0.30
a.e
8 0.20 6,623.63 0.04
ai
1 0.02 234.18 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
e
6,925 96.35 13,504,242.24 87.07
ea
190 2.64 682,677.41 4.40
ai
33 0.46 647,305.84 4.17
a
18 0.25 511,055.07 3.29
ie
15 0.21 116,953.33 0.75
ay
1 0.01 46,282.60 0.30
eo
5 0.07 1,579.14 0.01
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
i
9,718 97.26 24,972,954.70 97.33
ee
1 0.01 337,818.60 1.32
y
189 1.89 110,977.00 0.43
i.e
58 0.58 86,609.39 0.34
u
5 0.05 53,545.90 0.21
o
1 0.01 37,722.70 0.15
e
5 0.05 36,892.22 0.14
ei
10 0.10 15,862.87 0.06
ie
5 0.05 6,259.95 0.02
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
o
2,211 97.57 5,476,216.42 94.05
ough
15 0.66 224,260.72 3.85
o.e
2 0.09 46,725.79 0.80
oh
3 0.13 37,990.80 0.65
ow
4 0.18 19,647.35 0.34
oa
12 0.53 8,236.78 0.14
e
15 0.66 7,692.52 0.13
ou
4 0.18 2,148.66 0.04
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
a
1,240 74.47 3,898,726.28 83.95
aw
138 8.29 221,166.84 4.76
au
216 12.97 178,616.22 3.85
al
25 1.50 170,788.10 3.68
ea
23 1.38 84,734.22 1.82
augh
16 0.96 66,769.03 1.44
ah
4 0.24 19,356.51 0.42
awe
3 0.18 3,708.61 0.08
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
o
2,564 29.70 9,117,942.41 29.07
e
372 4.31 7,814,566.17 24.91
a
2,758 31.95 7,461,077.76 23.79
u
2,346 27.18 4,634,304.83 14.77
o.e
46 0.53 1,004,331.98 3.20
ou
300 3.48 632,008.38 2.01
i
117 1.36 217,295.53 0.69
au
8 0.09 126,000.83 0.40
oe
2 0.02 114,570.40 0.37
a.e
80 0.93 114,501.11 0.37
u.e
4 0.05 66,496.96 0.21
oo
9 0.10 38,821.13 0.12
ae
5 0.06 12,840.35 0.04
ah
17 0.20 11,734.20 0.04
y
3 0.03 464.74 0.00
ea
1 0.01 376.50 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
a.e
1,011 25.03 2,675,236.88 26.19
a
1,835 45.43 2,167,140.46 21.22
ay
239 5.92 1,754,647.34 17.18
ai
561 13.89 1,017,687.22 9.96
e.e
20 0.50 753,712.88 7.38
ey
29 0.72 719,284.18 7.04
e
187 4.63 395,455.41 3.87
ei
33 0.82 350,595.17 3.43
ea
52 1.29 309,467.11 3.03
eigh
32 0.79 46,337.37 0.45
aigh
4 0.10 17,594.28 0.17
et
22 0.54 3,914.88 0.04
ee
7 0.17 787.23 0.01
ae
6 0.15 770.22 0.01
ah
1 0.02 147.61 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
e
1,865 28.92 15,264,707.53 58.52
y
2,013 31.22 4,607,596.59 17.66
ea
656 10.17 2,130,742.03 8.17
ee
565 8.76 1,831,588.51 7.02
e.e
90 1.40 670,867.30 2.57
i
761 11.80 657,389.76 2.52
ie
317 4.92 434,235.59 1.66
ey
82 1.27 153,113.64 0.59
ei
46 0.71 153,035.34 0.59
eo
3 0.05 149,259.13 0.57
i.e
44 0.68 32,588.58 0.12
oe
3 0.05 716.35 0.00
ay
3 0.05 673.47 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
i
949 43.31 5,093,442.58 48.32
i.e
687 31.36 2,264,083.98 21.48
y
253 11.55 1,955,588.32 18.55
igh
167 7.62 865,722.09 8.21
ie
50 2.28 166,127.84 1.58
eye
14 0.64 109,888.85 1.04
ye
8 0.37 28,978.44 0.27
y.e
21 0.96 22,650.68 0.21
ia
11 0.50 14,538.49 0.14
eigh
4 0.18 8,285.49 0.08
ai
8 0.37 4,992.96 0.05
ay
5 0.23 4,532.79 0.04
ei
14 0.64 3,030.80 0.03
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
o
2,452 68.17 7,533,617.67 62.77
o.e
440 12.23 1,560,453.15 13.00
ow
236 6.56 1,165,023.97 9.71
ou
62 1.72 850,256.97 7.08
oa
243 6.76 200,313.91 1.67
oh
2 0.06 178,234.58 1.48
a
74 2.06 160,043.18 1.33
oo
25 0.70 127,868.10 1.07
oe
32 0.89 126,514.61 1.05
ough
9 0.25 94,046.97 0.78
eau
10 0.28 3,296.74 0.03
ew
4 0.11 2,304.45 0.02
au
4 0.11 741.15 0.01
eaux
3 0.08 84.87 0.00
aux
1 0.03 62.34 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
o
87 6.92 5,851,112.47 53.59
ou
57 4.53 3,213,170.86 29.43
oo
345 27.45 599,118.69 5.49
u
415 33.02 465,940.01 4.27
ew
104 8.27 304,469.98 2.79
u.e
123 9.79 154,717.24 1.42
ue
51 4.06 135,992.66 1.25
ough
4 0.32 117,003.02 1.07
ui
41 3.26 51,381.57 0.47
eu
22 1.75 13,296.64 0.12
oe
8 0.64 11,930.37 0.11
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
u
482 74.84 541,633.37 52.26
u.e
102 15.84 304,143.68 29.35
ew
20 3.11 70,858.57 6.84
ue
24 3.73 59,772.19 5.77
eau
3 0.47 56,845.34 5.48
eu
13 2.02 3,162.12 0.31
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
oul
7 2.83 844,557.35 42.43
oo
158 63.97 833,131.97 41.86
u
73 29.55 233,317.24 11.72
o
8 3.24 79,003.87 3.97
ou
1 0.40 372.43 0.02
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
ou
433 66.01 2,117,381.00 65.59
ow
219 33.38 1,107,931.18 34.32
ough
4 0.61 2,854.32 0.09
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
oi
158 61.72 234,107.42 53.61
oy
98 38.28 202,570.94 46.39
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
er
3,141 65.56 6,334,869.36 63.25
or
521 10.87 891,440.57 8.90
ur
394 8.22 680,572.17 6.80
ir
171 3.57 498,511.08 4.98
ere
2 0.04 442,426.19 4.42
ure
110 2.30 325,709.79 3.25
ar
169 3.53 232,781.77 2.32
re
96 2.00 226,077.38 2.26
ear
54 1.13 215,335.08 2.15
urr
51 1.06 60,810.90 0.61
our
35 0.73 35,192.55 0.35
orr
4 0.08 29,438.42 0.29
err
25 0.52 22,715.94 0.23
ro
5 0.10 11,432.20 0.11
irr
7 0.15 5,991.72 0.06
yr
6 0.13 2,024.81 0.02
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
ure
36 37.50 64,966.47 46.93
ur
48 50.00 55,447.02 40.05
eur
12 12.50 18,029.27 13.02
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
b
3,252 96.13 7,966,711.07 98.78
bu
18 0.53 56,621.18 0.70
bb
113 3.34 41,939.70 0.52
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
p
4,830 93.37 7,620,557.45 93.54
pp
343 6.63 526,573.30 6.46
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
g
1,667 87.28 4,130,255.80 94.35
gu
49 2.57 153,156.09 3.50
gg
155 8.12 61,628.38 1.41
gue
23 1.20 21,300.79 0.49
gh
16 0.84 11,262.78 0.26
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
c
4,698 67.76 6,962,825.70 58.52
k
1,259 18.16 3,795,456.75 31.90
ck
636 9.17 771,270.38 6.48
ch
183 2.64 199,748.95 1.68
cc
100 1.44 143,307.45 1.20
qu
18 0.26 11,602.81 0.10
que
22 0.32 10,136.16 0.09
cu
4 0.06 2,419.37 0.02
q
2 0.03 681.47 0.01
cch
7 0.10 500.75 0.00
kh
4 0.06 337.43 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
d
6,081 83.85 19,265,445.28 90.50
ed
1,031 14.22 1,825,049.05 8.57
dd
140 1.93 196,132.56 0.92
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
t
10,409 91.05 32,646,664.33 94.91
tt
444 3.88 895,438.03 2.60
ed
535 4.68 782,269.23 2.27
bt
15 0.13 46,579.45 0.14
th
10 0.09 12,934.33 0.04
tte
15 0.13 9,434.11 0.03
pt
4 0.03 2,906.58 0.01
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
f
2 0.10 4,137,188.65 43.92
v
1,724 82.73 3,412,584.87 36.23
ve
356 17.08 1,870,421.10 19.86
vv
2 0.10 111.77 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
f
2,278 80.92 7,325,298.19 89.74
ff
255 9.06 523,319.14 6.41
ph
255 9.06 174,815.56 2.14
gh
27 0.96 139,348.79 1.71
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
j
413 34.62 920,087.85 43.97
g
458 38.39 579,931.14 27.71
ge
165 13.83 413,942.86 19.78
dge
59 4.95 69,457.26 3.32
d
25 2.10 34,579.90 1.65
gi
20 1.68 34,206.17 1.63
gg
11 0.92 21,099.28 1.01
dg
40 3.35 17,356.33 0.83
di
2 0.17 1,959.21 0.09
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
ch
637 65.47 1,761,076.75 78.06
t
156 16.03 289,683.16 12.84
tch
166 17.06 151,227.65 6.70
ti
11 1.13 53,668.64 2.38
c
3 0.31 362.46 0.02
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
s
4,171 90.73 10,498,300.19 94.04
se
36 0.78 428,250.31 3.84
z
320 6.96 174,652.83 1.56
ss
11 0.24 27,114.95 0.24
ze
15 0.33 18,519.77 0.17
zz
40 0.87 12,425.36 0.11
x
4 0.09 4,662.92 0.04
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
s
7,980 78.38 16,177,373.64 79.39
c
900 8.84 1,453,443.27 7.13
ss
707 6.94 1,112,978.02 5.46
ce
305 3.00 997,530.35 4.90
se
142 1.39 461,377.07 2.26
st
42 0.41 94,823.09 0.47
sc
83 0.82 72,186.29 0.35
ps
22 0.22 6,525.75 0.03
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
si
79 60.31 93,840.24 50.19
s
29 22.14 85,838.68 45.91
ge
13 9.92 4,749.16 2.54
z
2 1.53 977.69 0.52
g
4 3.05 843.81 0.45
ti
2 1.53 415.73 0.22
ci
1 0.76 190.04 0.10
j
1 0.76 99.30 0.05
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
sh
802 39.86 1,840,374.15 55.95
ti
907 45.08 963,969.82 29.31
ci
91 4.52 150,755.62 4.58
ssi
64 3.18 120,613.14 3.67
s
18 0.89 106,956.32 3.25
ch
42 2.09 28,080.59 0.85
ss
14 0.70 26,957.54 0.82
sci
11 0.55 19,966.78 0.61
si
22 1.09 12,997.33 0.40
c
13 0.65 12,420.23 0.38
t
14 0.70 2,894.98 0.09
che
5 0.25 2,163.09 0.07
sc
4 0.20 820.54 0.02
sch
5 0.25 148.41 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
th
172 91.49 21,536,450.69 99.96
the
16 8.51 7,841.06 0.04
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
th
563 100.00 3,457,176.81 100.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
m
4,479 93.55 13,755,060.02 97.90
mm
243 5.08 220,261.30 1.57
mn
14 0.29 40,896.91 0.29
mb
49 1.02 32,837.05 0.23
gm
3 0.06 378.06 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
m
69 100.00 19,877.45 100.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
n
10,007 96.71 31,151,759.13 97.04
kn
53 0.51 630,319.44 1.96
nn
231 2.23 248,172.23 0.77
gn
55 0.53 71,132.37 0.22
pn
1 0.01 382.32 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
ng
2,626 86.27 4,131,952.09 82.90
n
412 13.53 841,613.37 16.89
ngue
6 0.20 10,445.03 0.21
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
l
6,155 88.13 11,632,145.79 75.76
ll
829 11.87 3,721,493.24 24.24
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
le
725 44.84 1,147,170.71 52.60
al
535 33.09 664,656.95 30.48
ul
69 4.27 121,476.56 5.57
el
133 8.23 107,974.75 4.95
il
41 2.54 52,355.78 2.40
l
47 2.91 33,273.12 1.53
all
32 1.98 27,606.61 1.27
ull
16 0.99 11,156.55 0.51
ell
7 0.43 8,365.94 0.38
ol
6 0.37 6,343.86 0.29
yl
4 0.25 397.22 0.02
ill
2 0.12 1.00 0.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
r
8,256 96.40 19,392,194.64 97.02
rr
221 2.58 427,409.43 2.14
wr
71 0.83 163,920.98 0.82
rh
16 0.19 4,538.41 0.02
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
h
1,148 98.54 8,982,844.13 94.15
wh
12 1.03 557,000.41 5.84
j
5 0.43 1,207.69 0.01
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
w
990 86.77 8,323,014.83 78.42
wh
114 9.99 2,254,493.87 21.24
u
37 3.24 36,167.07 0.34
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
o.e
7 100.00 647,174.45 100.00
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
y
118 55.14 4,509,285.71 95.68
i
93 43.46 202,403.32 4.29
j
2 0.93 721.60 0.02
ll
1 0.47 332.72 0.01
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
qu
287 95.99 381,642.40 95.79
cqu
12 4.01 16,765.52 4.21
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
x
549 99.28 716,540.66 99.70
xe
4 0.72 2,138.52 0.30
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
xi
6 60.00 12,089.55 65.94
x
4 40.00 6,245.41 34.06
Phoneme Grapheme Frequency (total) Frequency (%) Weighted Frequency (total) Weighted Frequency (%)
tz
9 42.86 3,290.41 45.83
z
4 19.05 2,095.03 29.18
zz
6 28.57 1,660.25 23.12
ts
2 9.52 134.37 1.87

Methodology

In our data we break each word into its phoneme-grapheme correspondences. We use two rankings to score their frequency: direct and weighted.

For direct ranking:
Frequency (total) - We count the number of times a correspondence occurs in each word in our list. If it is used more than once in a word, then it is counted for each occurrence.

Frequency (%) - The percentage of time that a phoneme is represented by a grapheme.

For weighted ranking:
We use two different word frequency lists to determine a word's frequency. First, we use a Project Gutenberg word frequency list from 2006 to get a baseline in written text. Since Project Gutenberg (PG) is limited to public domain books it does not have recent words like 'aliens' and 'radiation'. We used Open Subtitles, open source movie subtitles, as our second list since it includes recent movies and hence, modern words.

We multiply the Open Subtitles frequency by 4 to bring it in line with values from the Project Gutenberg frequencies and then average the two frequencies. We wanted common words like 'it' and 'that' to be roughly equivalent for both data sets.

Weighted Frequency (total) - We look at each word, then multiply the number of times a particular correspondence occurs in the word by the word's frequency, then we add all these values together for that correspondence.

Here's an example. This is the calculation for 'f' = /v/.
PG frequency for 'of': 33,950,064.00
Subtitle frequency for 'of': 1,847,884.00
Average frequency: (33,950,064.00 + (1,847,884.00 x 4)) / 2 = 20,670,800.00
Number of times 'f' = /v/ in the word 'of': 1
Weighted Frequency for 'f' = /v/ in the word 'of': 20,670,800.00 x 1 = 20,670,800.00

We repeat this calculation for the far less common word 'thereof' to get the weighted frequency of 15,143.25

Finally, we sum the weighted frequencies and divide by 5, the lowest frequency for all correspondences, to make the numbers more manageble.
Weighted Frequency (total): (20,670,800.00 + 15,143.25) / 5 = 4,137,188.65

Weighted Frequency (%): The percentage of time that when you come across that phoneme in text that it will be represented by that particular grapheme.

* These calculations are based on the count of phoneme-grapheme correspondences across 26,102 words as of May 2023.

Other References

For previous work in this area see Paul Hanna's paper Phoneme-Grapheme Correspondences as Cues to Spelling Improvement