Personality tests in hiring explained
2 minutes
Ben Schwencke explains what personality tests measure, why they matter in hiring, and how to get the most from them in your selection process.
Most hiring managers feel reasonably confident in their ability to read a candidate. After a good conversation, they often trust their instincts. The problem is that research consistently shows those instincts aren't very reliable — and the people who are hardest to read accurately are often the ones who've had the most practice presenting themselves well.
Personality tests don't replace good judgement. They sharpen it. By measuring behavioural traits that interviews can't easily surface — things like conscientiousness, resilience, and how someone responds to conflict — they give you a consistent, evidence-based layer of insight that applies to every candidate equally. This article explains what they measure, why that matters, and what you can realistically expect them to do for your hiring.
What do personality tests actually measure?
A good personality questionnaire measures stable behavioural traits — patterns in how people tend to think, feel, and act across different situations. The most widely researched and validated framework is the Big Five model, which covers traits like conscientiousness (how organised and disciplined someone is), emotional stability (how they handle pressure and setbacks), agreeableness (how they work with others), openness (curiosity and adaptability), and extraversion (social energy and confidence).
In a hiring context, these traits matter because they predict things that job performance depends on but that CVs and interviews rarely capture clearly: whether someone will stay motivated without close supervision, how they'll respond when things go wrong, and whether they'll genuinely engage with the team around them.
Why CVs and interviews aren't enough
CVs tell you what someone has done. Interviews tell you how they present themselves. Neither tells you much about how they'll actually behave once they're in the role, six months in, when the novelty has worn off and the real demands of the job kick in.
This gap is where most bad hires happen. The candidate who charmed you in two rounds of interviews turns out to be difficult to manage, disengaged, or a poor fit for the team culture. Not because anyone made a mistake, but because the tools used didn't measure what actually drives day-to-day behaviour. Personality assessments are specifically designed to fill that gap — consistently, objectively, and at scale.
The core insight
Interviews measure how well someone can describe themselves. Personality tests measure consistent patterns in how they actually behave. Both are useful — but only one tells you what's likely to happen after the offer is signed.
The key advantages of personality tests in hiring
They reveal performance that CVs can't predict
Some of the most valuable employee behaviours never appear in a job description — staying late to help a colleague, volunteering for a difficult project, maintaining quality under pressure. Research in organisational psychology calls this "contextual performance," and it's heavily driven by personality. Traits like conscientiousness and industriousness are among the strongest known predictors of job performance across almost every role — often stronger than years of experience. A candidate who scores highly on these measures is far more likely to be the person who brings consistent quality and goes beyond the minimum. A CV can't tell you that.
They help you find the right cultural and role fit
Poor job fit is one of the leading causes of early attrition. Someone might have the right technical skills but find the role too isolating, too high-pressure, or misaligned with how they naturally work. Personality data helps you match candidates not just to the skill requirements of a role, but to its behavioural demands — whether it suits someone independent and methodical, or someone energetic and people-focused. Getting this right leads to better engagement, stronger retention, and employees who genuinely want to be there.
They flag risk before it becomes an expensive problem
Every hiring team has experienced it: the candidate who interviewed brilliantly but turned out to be disruptive, difficult, or dishonest once in post. The challenge is that the most problematic behaviours — low integrity, poor emotional regulation, a tendency toward conflict — are often the hardest to spot in an interview, precisely because those candidates have learned to present well. Personality assessments measure these traits objectively, giving you a structured way to spot red flags before an offer is made rather than after.
They protect employee wellbeing
Some roles carry a heavy load — high client pressure, emotional demands, intense targets, constant change. Placing someone in a role that doesn't match their natural resilience and stress tolerance isn't just bad for performance; it can be genuinely harmful to them. Personality assessments measure emotional stability, adaptability, and stress resilience, so you can match candidates to roles they're genuinely equipped to handle — rather than discovering the mismatch after the fact.
They make your process fairer and more consistent
Every interviewer has blind spots. Without a structured assessment, hiring decisions are influenced by how much someone reminds you of a top performer, how confidently they came across, or factors that have nothing to do with the job. Personality questionnaires apply the same criteria to every candidate, which reduces the impact of unconscious bias and makes it easier to compare candidates on equal terms. This is particularly valuable for high-volume hiring, where interview time is limited and consistency is hardest to maintain.
We use Test Partnership's personality and strengths tests as a trusted element of our selection process. There is a comprehensive range of tests and the platform is extremely straightforward to use. If you need any assistance the support is great.
Are personality tests right for you?
If your hiring decisions currently depend mainly on CVs and interviews, adding a validated personality questionnaire is one of the most straightforward improvements you can make. The tests themselves take 15–20 minutes for candidates to complete, and the data they generate is immediately useful — giving you a structured, comparable profile for every candidate rather than a collection of subjective impressions.
They work across virtually every role type and seniority level, and they're most effective when used alongside cognitive ability tests — the combination gives you both the capacity to do the job and the behavioural fit to do it well. If you're unsure which tests are right for your specific roles, our team can help you choose.
Explore our personality assessments
See the full range of personality, behaviour, and soft-skills assessments available through Test Partnership — including how they work, what they measure, and which roles they're best suited for.
Primary author
Ben Schwencke
Chief psychologist at Test Partnership. MSc in Organisational Psychology with over ten years experience in psychometric testing.
Contributed to by:
