Self-Discipline Test: Grit, Willpower, and Follow-Through, Measured
Grit scales, growth mindset quizzes, marshmallow tests, locus of control inventories: psychology keeps finding the same engine from different angles. Underneath most of them sits the Conscientiousness domain of the Big Five plus a handful of neighboring facets, and those can all be measured at once, properly, on one validated instrument.
The IPIP-NEO-120 scores each piece independently. You do not get a verdict like "gritty" or "undisciplined"; you get percentiles on the specific traits these concepts are made of, which tells you where the engine is strong and where it leaks.
Where each concept lives in the profile
Grit is Achievement-Striving plus Self-Discipline: the drive to set hard goals and the persistence to keep working after the novelty dies. Duckworth's own research places grit squarely inside Conscientiousness.
Delayed gratification shows up twice, as high Self-Discipline and as low Immoderation, the facet that measures how hard impulses pull on you. Someone can resist the marshmallow through iron control or through barely wanting it, and the profile distinguishes those two people.
Locus of control maps closest to Self-Efficacy, the belief that your actions determine your outcomes. It is the single trait that most separates people who act on their results from people who file them away.
Growth mindset is not one facet; it rides on the pairing of Intellect, the appetite for learning, with the persistence facets above. The profile shows whether your curiosity has the follow-through to compound.
Temperament, if you want the adult version of that word, is the full readout of the 30-facet OCEAN personality test: all five domains, no types, continuous scores against norms for your age and sex.
What you get
Five domain percentiles free, immediately. The extended profile opens all six Conscientiousness facets alongside the other 24, plus 20+ computed patterns including perfectionism and overthinking, the two classic failure modes of high-discipline profiles. If you read books in this space, the facet scores plug directly into our analyses of Grit, Atomic Habits, and Deep Work.
How it works
120 statements rated 1 to 5, about 15 minutes. Scores convert to percentiles using the IPIP-NEO validation norms, adjusted for age and sex. The instrument is the public-domain research version of the NEO-PI-R, validated against it above r=0.90. Results are private unless you share them.