ISTJ Vs INTJ: The Difference Between The Two Personalities

You think the difference between ISTJ and INTJ lies in one letter?

Well, you’re technically right.

But one letter makes a whole world of difference.

As an INTJ, I was quite surprised to learn how different ISJTs are from us.

And in this article, I’ll share that knowledge with you.

Here’s the ISTJ vs INTJ showdown.

What is ISTJ

Statistically speaking, ISTJ is one of the most common personality types in the world. To put it differently, most of us probably know a person or two with this personality type.

So, what are they like?

They’re reserved and sensible, with great attention to detail. They’re also systematic and with clear goals and intentions. 

In fact, to get a clear overview of what kind of personality ISTJ is, it’s best to look at its cognitive functions. Sorted by dominance, here are the functions that ISTJ use:

  • Introverted sensing – this function allows them to be very perceptive and focused on the present. But they can also vividly recall past memories in order to make an informed decision.
  • Extroverted thinking – when making a decision, ISTJs are guided by logic rather than feelings.
  • Introverted feeling – ISTJs are sensitive to the feelings of other people. This often impacts their decision-making process.
  • Extraverted intuition – their least developed function is what makes them enjoy new experiences and ideas in life.

What is INTJ

INTJ, on the contrary, is one of the rarest personality types.

But just like ISTJs, people with the INTJ personality type are also goal-oriented and methodical in achieving them. They’re also very curious, which is why they’re considered to be “walking encyclopedias.” 

INTJ’s cognitive functions (in order of how well they’re used) are:

  • Introverted intuition – INTJs have an easy time processing information through patterns. This makes it easy for them to see the big picture at any point.
  • Extroverted thinking – INTJs perceive the world around them with logic and rational reasoning, not feelings.
  • Introverted feeling – When developed, this function helps INTJ become more emotionally aware of themselves and others.
  • Extroverted sensing – this function allows INTJs to be preset and perceive their surroundings with senses.

ISTJ vs INTJ: How to Tell Them Apart?

While at first glance you might think otherwise, ISTJ and INTJ are very different personality types. In this section, we’ll cover everything that sets them apart.

Dominant cognitive function

Introverted intuition is the dominant function of an INTJ. In other words, it’s kind of like their trademark. People with this personality type always have the bigger picture in mind, so everything they do leads toward the goal.

But while they’re focused on the future, ISTJs are the ones that are more in the present. ISTJs’ dominant function is introverted sensing. This helps them focus on facts and details rather than on abstract concepts like INTJs would.

Of course, both perspectives have their flaws.

Because they pay more attention to details, ISTJs might have a hard time “seeing the forest from the trees.” With the INTJ type of personality, it’s quite the opposite. By being so focused on the big picture, they tend to oversee the “trees the forest consists of.”

Dealing with authority

INTJs aren’t the ones to blindly follow the rules. They look for reasoning in all things, and that’s true in the case of authority as well.

In other words, an INTJ will obey rules only if they agree with them

Putting this attitude in the workplace, an INTJ will always speak their mind if they think the manager is wrong. One thing INTJs can’t stand is micromanaging, especially if they don’t agree with the rules the boss is trying to impose on them.

ISTJs, on the other hand, don’t have such a strong tendency to question everyone, especially when it comes to authority. They believe in hierarchy, so naturally, they think that those above them probably know more about the matter.

So they’re more likely to follow the rules, even if they’re not 100% on the fence with them.

Social interactions

Both of these personality types are introverts, so they probably won’t be the loudest ones at group gatherings. Still, there are some pretty obvious differences in their ways of communication.

INTJs are lone wolves, and interaction with other people can be quite draining. That’s why they prefer to be very concise and straightforward when communicating with others.

In order to be completely understood, INTJs will use analogies and figures of speech to get their point across. 

ISTJs, on the contrary, prefer being literal in communication. They have a great ability to recall past events, which allows them to be so concrete in interaction with other people.

And unlike INTJs, people with the ISTJ personality type value community. That means they’re actually happy to be surrounded by other people and engaging with them, even as introverts.

Dealing with conflicts

Both of these personality types will enjoy a good intellectual debate. 

But INTJs don’t mind going all in and arguing about topics they have strong opinions about. And if that leads to a conflict, so be it. INTJs will fight for what they believe to the very end.

ISTJ person, on the contrary, will try to avoid conflict. In fact, they might not even engage in a debate that’s likely to go the wrong way, as they prefer to keep things more peaceful.

Of course, that doesn’t mean they’ll stay silent when it comes to people they’re close with. In case a conflict is with their partner, they’ll do everything in their power to deal with it.

Working in teams

One thing that’s very clear is that INTJs don’t really do well in teamwork.

As lone wolves, people with this personality type prefer working on their own. They’re very goal-oriented, so they’re focused on the job until it’s done. And they don’t need help from others, which in most cases will only slow them down.

As an INTJ might say, “if you want something done, it’s best you do it yourself.”

ISTJs, however, like being a member of a team. Like INTJs, people with ISTJ personality types are task-oriented. But they value structure and best work in the company of like-minded people. 

ISTJs aren’t planners but doers, so they don’t mind if they’re simply following others’ ideas.

Are ISTJ and INTJ Similar in Any Way?

men in similar suits

I’m sure by now you might be wondering – is there anything similar about these two personality types?

And the answer is yes.

In fact, their starting point for action is, for the most part, the same. However, they use different methods to achieve the ultimate goal. 

Let’s go over each action individually to explain what I mean.

The drive

Both of these personality types are very driven. They know what they want and will strive towards that without distractions.

They use a different approach, though. INTJs are focused on the future, while ISTJs like to stay in the present. But what’s the same is the drive that keeps them focused on what they’re doing.

In the workplace, you want them both. You can rest assured that both INTJ and ISTJ will get things done before the deadline.


Both INTJ and ISTJ always want to do their best, regardless of the matter. This is due to their great attention to detail and ability to structure their lives around rules.

These personality types are very thorough and won’t move up a step until they’re completely satisfied with their work. And while it might take them longer to achieve the goal, they’ll stay focused on it until the end.

Dealing with emotions

Both personality types are introverts, so they’re not easy on dealing with emotions – their own and the emotions of others.

INTJs and ISTJs are both seen as cold and emotionless, which is far from the truth. But these two personality types try to express their emotions in a more practical way

So while you might not hear deep emotional words coming out of INTJs’ or ISTJs’ mouths, rest assured their actions will do the work.

To Sum Things Up

As you can see, ISTJ and INTJ personality types have some prominent distinctions.

INTJs love their independence and freedom, while ISTJs prefer having structure and hierarchy.

That’s why ISTJs will enjoy being surrounded by people, while INTJs will remain out of the circle.

But while different, these two personality types do great together – especially in the workplace.

Together, they complete the circle and bring everything the surrounding needs into one place.

Don’t quite understand the INTJ personality type? Here’s our article about the strengths and weaknesses of INTJs.