Five-Factor Model scoring as a service
The most-validated personality model — Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism — as five continuous dimension scores via three REST calls. X-API-Key auth, server-side scoring, results attributed to your org.
JobCannon's Big Five API exposes the Five-Factor Model (FFM / OCEAN) as a live REST service. POST /api/v1/assessments with { test: "big-five" } starts a session and returns the question set; POST /api/v1/assessments/{session_id}/complete submits answers and returns { result_id, top_result, scores } where scores contains all five OCEAN dimension values — Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism — as normalised continuous scores. GET /api/v1/assessments/{session_id}/questions re-serves the question payload at any point during a session (scope assessments:read). Authentication is a single X-API-Key header (jck_live_…, scopes assessments:send / assessments:read, SHA-256 hashed at rest) with no OAuth exchange. Scoring is deterministic and server-side, with directional-item handling and degenerate-submission rejection. Every result is attributed to the partner organisation via api_org_id. The five continuous dimension scores are suitable for rendering radar/bar profiles in HR-tech and coaching products, as normalised inputs to downstream ML models or team-composition algorithms, and for research data collection. Live on the Scale tier ($199/mo) with a monthly allotment then $2/assessment overage; white-label partners can move to revenue-share.
Continuous dimension scores, not just a type label.
Deploy Big Five alongside personality, EQ, or aptitude instruments for a fuller candidate or coaching profile.
For HR-tech, research, and coaching platforms embedding the Five-Factor Model
The Big Five API is an instrument-specific entry point into the broader psychometric API, which covers the full scientific framing alongside other validated frameworks. For the three-call lifecycle, auth details, and all 126+ instruments, see the Assessment API reference. All institutional features are on the JobCannon for Business hub.
If your platform also needs career-interest data alongside trait scores, see the RIASEC API. For EQ alongside personality, see the EQ API. Teams embedding the full assessment experience under their own brand should also review white-label theming and the personality test API overview.
Live on the Scale tier ($199/mo) with a monthly assessment allotment; additional assessments are $2 each. Research institutions and coaching platforms should ask about partnership pricing. White-label partners who embed and resell OCEAN profiles can move to a revenue-share.
Always free for micro-teams
For solo coaches and small HR
For startups, teams and HR
For agencies, L&D and scale-ups
For 200+ person companies
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Tell us your use case — HR-tech, research, coaching — and expected monthly volume. We respond with a key, the endpoint reference, and a technical onboarding plan.
The Five-Factor Model (FFM / Big Five / OCEAN) is the most empirically validated personality framework in occupational psychology. Decades of meta-analysis link Conscientiousness to job performance, Agreeableness and Extraversion to team-role fit, Openness to creative-role success, and Neuroticism (or its inverse, Emotional Stability) to burnout risk and resilience. Unlike type-based models, the Big Five returns continuous dimension scores, which means you can normalise them against population norms, compute similarity indices for team composition, or feed them into downstream ML models as features.
POST /api/v1/assessments/{session_id}/complete returns { result_id, test, top_result, scores, question_pool }. For the Big Five instrument, scores contains all five OCEAN dimensions as normalised values (Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism). top_result is the dominant trait label — the highest-scoring dimension — useful for a headline summary. Your product renders the dimension breakdown however makes sense for your use case: radar chart, bar profile, descriptive copy, or raw values for a model input.
POST /api/v1/assessments with { test: "big-five", locale?, external_user_id? } starts a session and returns { session_id, questions[] }. GET /api/v1/assessments/{session_id}/questions re-serves the question payload if your UI needs it again (scope assessments:read). POST /api/v1/assessments/{session_id}/complete with { answers: number[] } submits the answer vector and returns the scored result. Scoring is server-side and deterministic — the same engine used on jobcannon.io.
Scoring is deterministic and server-side — clients submit answer indices, the scoring key lives on the server. Directional (socially-desirable) item handling is built in, so inflated Agreeableness or Conscientiousness self-reports are dampened by the engine. Degenerate submissions — an untouched default answer vector that would produce a superficially valid-looking result — are rejected before a result row is written. This is the same integrity layer protecting the consumer product.
Yes. The scores payload returns continuous numeric values per dimension, not just a categorical type label. You can normalise them, compute composites, or pass them directly into a downstream classifier or recommendation system. The result_id persists the result to your organisation via api_org_id, giving you a stable reference to join against your own data.
Every request carries a single X-API-Key header. Keys are issued per organisation (format jck_live_…), scoped to assessments:send and assessments:read, and SHA-256 hashed at rest. There is no OAuth exchange. Sessions are short-lived signed tokens returned by the start call — no session store on your side.
The API is live on the Scale tier ($199/mo), which includes a monthly assessment allotment. Assessments over the cap are $2 each. Research institutions and coaching platforms should ask about partnership pricing. White-label partners who embed and resell OCEAN profiles can move to a revenue-share model.