Arches are rare among the broad families
The study counted 4,340 fingerprint impressions from 434 people. Loops accounted for 2,592 impressions, whorls for 1,542 and arches for 206. That places arches at 4.75% when the unit is one impression.
The participants were Sinhalese university students in Sri Lanka. Recruitment used provincial population quotas, and collection ran from January 2010 to January 2012. Those details identify the study population; they do not turn a student sample into a worldwide estimate.
Subtypes change the question
Loops, whorls and arches are broad families. The paper further separates them into eight subtypes, including radial and ulnar loops, plain and tented arches, and several whorl patterns.
Accidental whorls are the least frequent subtype in each published sex-specific table: 1.10% among male impressions and 1.38% among female impressions. That does not contradict arches being the smallest broad family. The two answers use different levels of classification.
Choose a classification above before comparing a particular pattern. The subtype views preserve the paper’s rounded percentages. They do not fabricate exact counts by reversing those rounded values.
Fingerprints are not people
All ten fingers were recorded for every participant. A person could contribute multiple impressions of the same family or different families across their hands. Therefore, 206 arch impressions do not mean 206 different people with arches.
The same issue prevents multiplying single-finger percentages to estimate the chance of someone having ten arches or ten whorls. That calculation would require a model of how patterns occur together across fingers, which this explorer does not provide.
What the ranking does and does not identify
A pattern family groups many different prints. Its frequency cannot determine whether a particular detailed fingerprint matches someone else’s, nor does this page infer a personality or health condition from a pattern.
All counts and percentages come from Wijerathne and colleagues, Journal of Physiological Anthropology (2013), specifically its results and Tables 1–2. The downloadable rows retain the unit, population and classification. For a separate question about hands, compare the broader evidence on left-handedness.
Good questions
Are arches the rarest fingerprints?
Arches were the least common of the three broad pattern families in this study: 206 of 4,340 impressions, or 4.75%. A finer classification produces a different answer.
What is the rarest fingerprint subtype?
Accidental whorls had the lowest published frequency among the eight subtypes in both sex-specific tables: 1.10% of male impressions and 1.38% of female impressions. These describe this study, not all fingerprints worldwide.
Does 4.75% mean that 4.75% of people have arches?
No. Every participant contributed ten fingerprints. A share of impressions is not the share of people with at least one arch.