About the Kraepelin Continuous Arithmetic Test
Kraepelin's Arithmetic Test required subjects to add pairs of single-digit numbers continuously for periods of 15-60 minutes, with brief rest periods. The test produced a "work curve" showing changes in speed and accuracy over time, revealing patterns of fatigue, recovery, and attention drift.
Kraepelin used the test to differentiate psychiatric conditions: depressed patients showed flat low-output curves, manic patients showed initial high output followed by collapse, neurasthenic patients showed exaggerated fatigue. The test became standard in early 20th-century European psychiatry.
A modified version, the Uchida-Kraepelin Performance Test, remains in widespread use in Japan today for vocational selection by railway companies, airlines, and the Japan Self-Defense Forces. It is among the most-administered psychological tests in the world, with millions of administrations per year.
The 0 subtests
Take the full 60-item test
Kraepelin Continuous Arithmetic (1895): rapid mental addition under time pressure. 60 simple addition problems; complete as many as you can. Original test required 15-60 minute work sessions; web version is self-paced.
No data leaves your browser.
Read the Original
The following are legitimate free or borrowable full-text sources for this test or its primary documentation:
Source
All test materials and historical content on this page are transcribed from:
Kraepelin, E. (1895). Der psychologische Versuch in der Psychiatrie. Psychologische Arbeiten, 1, 1-91.
Emil Kraepelin (1856-1926) was a German psychiatrist, the founder of modern scientific psychiatry. His arithmetic test was the first systematic measure of sustained cognitive work.
Want a modern IQ score?
The Kraepelin Continuous Arithmetic Test is a historical artifact. For a contemporary IQ score using modern norms, take our modern full IQ test.
Take the Modern IQ Test