553 FORMS
Learn 15 verbs, they said
We measured the 15 irregular Spanish verbs every course tells you to memorise against 1,141,520 words of real Spanish. They turn up in 553 different forms.
That is the number nobody prints.
10 TEXTS
What we actually measured
Ten Spanish-language books from Project Gutenberg, 1,141,520 running words, 57,603 distinct word forms. Conjugation tables came from curated Verbiste templates, never guessed.
Don Quijote is the biggest text in it.
A FLOOR
Every number here is conservative
The corpus is not grammatically tagged. If a form is also a noun or a function word, we dropped it. Vino is both 'he came' and 'wine', so vino is gone. The real counts are higher.
We would rather undercount than guess.
37 EACH
You do not learn a verb
Spread across fifteen verbs, 553 forms is an average of nearly 37 distinct faces each. Tener alone appeared in 47. The lists are right that these verbs matter. They are wrong about the unit.
You meet a form, not a verb.
24 FORMS
Half the work, one sheet of paper
We ranked all 553 forms by how often they really appear. Twenty-four of them cover 50% of every time those verbs show up. Not 24 verbs. Twenty-four individual words.
86 forms cover 80%. 147 cover 90%.
ES, HABIA
The three that lead everything
Es appeared 4,967 times, había 3,706, dijo 2,603. By the time you know those three you have covered a fifth of everything these fifteen verbs do.
Books are full of people saying things.
THE PAST
Courses teach the wrong tense first
Nine of the twelve commonest forms we found are past or narrative: había, dijo, estaba, tenía, iba. Courses drill the present tense for months. Books are written in the past.
No vosotros anywhere in the top twelve.
21 SHARED
Ser and ir are the same verb in the past
They share 21 forms outright. Fue a la casa is 'he went to the house'. Fue una casa grande is 'it was a big house'. Same word, and only the sentence tells you which.
Best value in Spanish grammar.
71.4%
Five forms per verb, then stop
Across the fifteen verbs, each one's five commonest forms carry an average of 71.4% of everything it does. For ser it is 94.1%. The other thirty-odd forms split the rest.
Learn the rest later, from reading.
SHORT WINS
It was never about irregularity
A two-letter verb form appears 814 times on average in our corpus. At four letters it is 37. At twelve letters, 2.3. It falls at every single step, without one reversal.
Length beats conjugation class as a clue.
154 MILLION
A bigger corpus said the same
Fratini, Acha and Laka tested this on CREA. Irregular forms looked 2.6 times more frequent, but once a few extreme outliers were removed the correlation vanished entirely. The length effect survived.
Frequency and irregularity are independent.
THE LIST
Start with 24, not 553
Our corpus is literary and old, so it will not tell you what a taxi driver in Bogota says today. But the shape holds: a few forms do most of the work, and the short ones win.
Tap through for the full ranked list.
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