IPIP-NEO (120-Item)

The IPIP-NEO-120 (Johnson, 2014) measures the full Five Factor Model hierarchy — five domains and thirty facets, four items per facet — with public-domain items selected from Goldberg's IPIP pool. Johnson developed it so the complete 30-facet profile could be measured in a public-domain instrument of practical length.

The thirty-facet architecture comes from Costa and McCrae's Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae, 1992), which consolidated the five-factor model into a working hierarchy: five domains — Neuroticism, Extraversion, Openness, Agreeableness, Conscientiousness — each articulated into six facets. Its authority rested on a sustained validation program showing the five factors converge across instruments and across self- and observer-ratings (McCrae & Costa, 1987).

Because the NEO PI-R is proprietary, Goldberg (1999) assembled a parallel public-domain pool — the 300-item IPIP-NEO — measuring constructs similar to its thirty facets; John A. Johnson then administered that pool to very large web samples and selected the best-performing four items per facet to produce the IPIP-NEO-120 (Johnson, 2014). Kajonius and Johnson (2019) subsequently examined its five-factor structure in a public dataset of more than 320,000 respondents.

What is administered here is the public-domain IPIP representation of the NEO hierarchy, not the NEO PI-R: the items are original IPIP statements keyed to constructs similar to the NEO facets, so scores here are not scores on the NEO PI-R, and its proprietary norms and manuals do not apply to this form.

Domain scores summarize their six facets each, and every facet is reported against the reference values shown in the norms section. As with all IPIP inventories, the items are free to administer verbatim, which keeps this profile fully reproducible.

The notes below are reproduced from the platform's psychometrics register for this instrument — the same source-cited reliability, validity, and norms text that accompanies its downloadable report.

Johnson (2014) reports Cronbach's alphas for the 30 facet scales of the IPIP-NEO in a large online sample (N = 320,128): median facet alpha = .77, range .62–.87. Domain composites formed from 6 facets each show higher reliability.

The IPIP-NEO-120 facet scales show good convergent validity with the corresponding NEO PI-R facets (mean r ≈ .73) and the factor structure replicates the five-domain model. Facets predict external criteria (e.g., N facets predicting anxiety disorders, C facets predicting academic performance) comparably to proprietary measures (Johnson, 2014).

Population percentiles for the 30 facets and 5 domain composites are derived from Johnson's (2014) published reference sample (N = 320,128). Scores are expressed as percent-of-maximum on the 1–5 item scale; published M and SD from Table 2 of Johnson (2014) enable the population-percentile comparison shown on the result page.

“Worry about things.”

Illustrative only. During administration items are presented one screen-set at a time; response-key direction is never shown to respondents.

Item responses are summed within each scale (reverse-keyed items recoded first) and expressed as a population percentile against the cited reference sample, with a reliability-based confidence range where α is published.

Kajonius, P. J., & Johnson, J. A. (2019). Assessing the Structure of the Five Factor Model of Personality (IPIP-NEO-120) in the Public Domain. Europe’s Journal of Psychology, 15(2), 260–275. https://doi.org/10.5964/ejop.v15i2.1671 — Large (N = 320,128), self-selected online volunteer sample; not nationally representative (Openness and Altruism facets may be elevated). Facet scores: 4-item sums, range 4–20. Domain scores: mean of the six facet sums, range 4–20.

Johnson, J. A. (2014). Measuring thirty facets of the Five Factor Model with a 120-item public domain inventory. Journal of Research in Personality, 51, 78–89.