The INTP and INFP are a pair of kooky, tireless rebels (not by choice, but by nature) who have little care for rules or regulations, and happily march to the beat of their own drums. Honest and unapologetically individualistic, these types have zero interest in abiding by the system or fitting the mold.

Fiercely independent and innovative, INTPs and INFPs are no strangers when it comes to depression or anxiety. They often crumble and crash under strict deadlines, constant scrutiny, or torturously specific details. As Intuitive Perceivers (NPs), they prefer large-scale thinking without constraints or a definitive end result.

Since these two types in the 16-type personality system share the same auxiliary (Extraverted Intuition, or Ne) and tertiary (Introverted Sensing, or Si) functions, they can resemble each other at first glance. However, their respective dominant functions (Introverted Feeling, or Fi in INFPs, and Introverted Thinking, or Ti, in INTPs) are very different.

INFP vs. INTP: Key Differences

From the most to least dominant in strength, here are the INFPs and INTPs respective function stacks:

INFP:

• Introverted Feeling (Fi)

• Extraverted Intuition (Ne)

• Introverted Sensing (Si)

• Extraverted Thinking (Te)

INTP:

• Introverted Thinking (Ti)

• Extraverted Intuition (Ne)

• Introverted Sensing (Si)

• Extraverted Feeling (Fe)

Below are some clues to help you further tell the INFP and INTP apart.

1. Fixed Morals vs. Open to Interpretation

The INFP values authenticity above all else, and abhors cognitive dissonance. Their moral compass is stone-cold rigid, even if they appear carefree and tolerant toward others’ opinions. They will not budge, no matter how compelling the arguments might be — the most important factor of consideration is their own feelings and stances about a topic. They can nod or listen attentively, as they respect differing opinions, but won’t sway from their securely anchored values. INFPs say what they mean, and mean what they say.

The INTP is far less grounded in this sense — and will likely have an intricately blended worldview spanning several philosophies or religious doctrines. This naturally makes them especially drawn to agnosticism, as it may seem illogical to confirm anything subjective and unable to prove (or disprove). Debates can get very heated, but their stances can definitely get shifted if the arguments are convincing enough.

2. Fiction vs. Non-Fiction

Inner worlds of INFPs are bursting with colors, dreams, and fantasies. They’re especially drawn to stories with complex, intriguing characters that defy expectations (due to primary Fi). In video games, this means interesting storylines that evoke emotion and resonance. The most important part of any media is to identify with a part of it and see how it can play out and intertwine with their lives.

INTPs, in contrast, prefer non-fiction as there are no complicating feelings and a slew of relationships to figure out. They may find their noses in a science magazine, glossary, or appendix of a textbook. They’re also suckers for in-depth, well-researched opinion pieces, as they’re open to differing viewpoints. With fiction, they appreciate it more if there are some real-life elements integrated into the plot. How-tos and walkthroughs are also right up their alley.

3. Hidden Fear of Self-Sabotage vs. Incompetence

The INFP is fiercely loyal (a ride-or-die kind of friend) and has a deep-seated fear of losing loved ones through conflicts or the slow, gradual process of drifting apart. Separations and changes hit extremely hard for this idealistic type. Without the opportunity to express their true self and putting on a mask, they will begin to combust internally, until an explosion ultimately arises. These wounds, contrary to the adage, pierce more deeply with time and unless transferred to a safer outlet (e.g. journaling or art) — the pain may resurface years later. Healing happens when they realize the past can be reframed as a lesson and brighter days lie ahead.

The INTP, on the other hand, will get stuck and become frustrated when they believe they’re wasting their potential. Sometimes this shows up as arrogance or a sense of “I-know-it-all-already” in immature cases and will incessantly defend their intelligence due to the lack of self-efficacy and confidence. They may withdraw and seemingly shy away from debate (and people in general) when they want to protect their ego, which may get out of hand in unhealthy types. When their intelligence is undermined or thrown under the bus, they’ll go ballistic internally (but remain calm and collected on the surface).

4. Under Stress: Workaholic vs. Emotional Wreck

The grip function of the two types differs drastically. When both are under extreme conditions, they’ll behave in a way unnatural to their natural preferences. As for the INFP, common behaviors include excessive working, exercising, or socializing to distract, numb, and block out whatever’s on their mind. This may present itself to those unknowing of the true situation like a burst of productivity or motivation when in reality, it’s a defense mechanism linked to escapism.

The INTP has the potential to erupt with anger and may even cry a river during times where Ti, Ne, and Si have all failed in the grand course of events. Desperate measures now enter the scene. Extraverted Feeling (Fe) as mentioned before, will be quite underdeveloped and forge a good fight. They will hit the “isolate self from everyone” button faster than you could blink and may develop a hefty case of trust issues along with stress.

5. Creation vs. Analysis

Creativity paired with eccentric ways of thinking are hallmarks of these two types. However, their execution is quite different. Although both are highly process-focused, the end result is quite different. The INFP’s tattoo of happiness has authentic, conscious creation etched in it. The ongoing process of self-discovery and creativity is one that fulfills their souls. And you bet they’re in it for the long run.

Analysis is next to synonymous with INTPs as they’re constantly in their heads, thinking. Gathering, streamlining, and critiquing data is right up their alley and they’ve got a sharp eye for illogicalities. Although they may enjoy creating things out of the blue, their true skill lies in thinking objectively (for all you psychology enthusiasts — it’s the second cognitive processing route) without being clouded by emotions.

6. Comfort vs. Anti-Boredom

Soft, tangible things draw INFPs in like a moth to a flame (their choice of partners, however, may not reflect this). Warm hugs, adorable animals, and stories that tug at their heartstrings are what makes their world go round. Their tertiary function, Si, marries with primary Fi to be loyal lovers of the common good and inner joy.

Losing a sense of their bodily needs is all too familiar with INTPs. Whether it comes to comfort, they are much more lenient and nonchalant. Often times they’ll be oblivious to their health until they come face-to-face with warning signs. They seek mental novelty, throwing themselves in different directions to avoid succumbing to boredom. This stimulation could, however, be helpful when their interests strongly align with their work or studies.

Closing Thoughts

The mighty world of inventions and progressive thought would be lackluster without the open minds and creative talents of the INFP and INTP. They may spend a longer time carving out their path and finding their happy place in the world, but once they do — watch out — it’s full steam ahead!

The striking similarities and intriguing differences between the two types could potentially create a powerful team that withstands the test of time. With the power to focus intensely and become modern autodidacts, it’s an exciting era for the INFP and INTP to flourish and thrive in.