ISTJ: The Investigator | Personality Description



Personality tests are a great tool to learn more about yourself. And because we live in the digital age, most personality tests are available for you to look at online. While there have been several tests you can dive into, a popular test that is trusted and used by many is the Myer’s Briggs personality test. This test divides personality into 16 groups –each with a specialized acronym that reveals the inner workings of each personality. Today, we are going to be going over the ISTJ personality, also known as the investigator.

Overview of the ISTJ

ISTJ stands for Introversion, Sensing, Thinking, and Judging. As an investigator, the ISTJ personality is someone who is naturally reserved, practical, and responsible. And, because they are introverts, they tend to feel emotionally drained after socializing with others. As a result, they enjoy spending time alone to recharge and center themselves.

Furthermore, the ISTJ personality would instead focus on the more minor details of life rather than the larger picture. Additionally, these individuals use logical thinking to make decisions rather than their emotions and prefer structure and organization over going with the flow. Compared to other personalities in the Myer’s Briggs test, the ISTJ personality accounts for 12% of the population and is the third most common personality type.


Furthermore, like all personalities, the ISTJ has many strengths. Let’s take a closer look at some of these.

Loyal: Individuals with this personality type have an instinct to protect those they care about. Therefore, they often find themselves committed to defending others, whether in their line of work or their personal life.

Perseverance: It is unlikely that you will see the ISTJ give up on something they are passionate about because these individuals are admirable preservers. Therefore, they use this trait to achieve their goals and remain competitive individuals in their careers.

Calmness: When it comes to stressful situations and emergencies, rather than run away from the problem, ISTJs are the ones to run towards it. They have an incredible ability to remain calm and logical in times of need, making them role models for others.

Knowledgeable: Overall, these individuals are ones with extensive breadths of knowledge. As they are natural investigators, they seek the truth and use their curiosity to uncover new information.


Moreover, while ISTJs holds many impressive strengths, they are human at the end of the day. Let’s take a look at some of the weaknesses of these individuals below.

Stubborn: As this personality type is loyal to the people they love and the causes they support, they can also be very stubborn to change. As a result, they believe tasks should be handled in one way only, and everything must be done accordingly to their liking.

Carelessness: Because the ISTJ personality is inherently logical, they tend to ignore the emotions of others. Therefore, they can come off unkind and inconsiderate to people’s feelings in their work and personal life. Thus, they can experience problems with the interpersonal relationships they have.

Judgmental: Although ISTJs handle stressful situations well, they can also become judgmental towards others if they do not believe they are addressing the problem the right way. Therefore, they can become very blunt and negative.


Healthy vs. Unhealthy ISTJ

 Furthermore, while many ISTJ personality types live healthy, balanced lifestyles, others find harmony in their emotions. Therefore, let’s take a look at the differences between a healthy vs. an unhealthy ISTJ below.


  • They feel comfort in knowing who they are
  • Will not go out of their way to prove they are right all the time
  • Open to the perspectives of others
  • They do not need to defend themselves or their image
  • They can readily admit when they have made a mistake
  • Are more empathetic towards others


  • Very defensive in moments they feel insecure
  • Can be very nagging towards others when they don’t get their way
  • They become depressed quickly, leading them to complain about life
  • May experience physical symptoms of stress
  • Sometimes these individuals can come off as arrogant and egotistical


Moreover, let’s compare what the ISTJ-A vs. the ISTJ-T is. The ENFJ-A is also known as the Assertive Investigator, while the ENFJ-T is the Turbulent Investigator. The assertive personality tends to be more flexible to changing circumstances, while their turbulent counterparts need stability to feel secure and comfortable in their lives. Furthermore, the assertive investigator is more likely to avoid confronting their feelings compared to the turbulent investigator. As a result, they can appear more closed off and cold. Additionally, the assertive ISTJ is more likely to be confident in themselves, while the turbulent ISTJ experiences self-doubt regularly.

ISTJ’s in Relationships

Furthermore, when in a relationship, ISTJs are very reliable and loyal to their partner. They enjoy providing stability for their family and prefer to address conflict as soon as it arises. Moreover, they enjoy being honest with their partner and can accept constructive feedback as well. However, they can have trouble being empathetic and understanding when their partner is upset and have difficulties becoming emotionally vulnerable.

Want to take a personality test used by big companies like Coca-Cola, AT&T, and Boeing? Take our free DISC personality test today!

 Best Careers for ISTJ Personality Type

Moreover, as the ISTJ personality is admirable and responsible, they excel in work environments that allow them to take charge and help others. Here are some of the best-suited careers for these individuals.

  • Surgeon
  • Accountant
  • Lawyer
  • Military Leader
  • Judge
  • Police Officer
  • Auditor
  • Financial Examiner
  • Claims Adjuster
  • Purchasing Agent
  • Probation or Corrections Officer
  • Tax Examiner or Collector
  • Statistician
  • Aerospace Engineer
  • Scientist
  • Forensic Science Technician
  • Airline or Commercial Pilot
  • Pharmacist
  • Optometrist

Famous ISTJ’s

Lastly, as a result of their ability to thrive in demanding environments and situations, many individuals with the ISTJ personality have gained fame because of their actions. Do you recognize any famous ISTJs below?

  • Elizabeth Warren
  • Alfred Hitchcock
  • Annie Leibovitz
  • Dorothy Day
  • Denzel Washington
  • Natalie Portman
  • Condoleezza Rice
  • Jeff Bezos
  • Angela Merkel
  • Mark Zuckerberg
  • John D. Rockefeller
  • Harry Turman
  • Queen Elizabeth II
  • Warren Buffett
  • Queen Victoria
  • George H.W. Bush

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