Knowledge, wisdom and the ability to think quickly. A high Intelligence is important for any character.Fallout in-game description

Intelligence is one of seven primary statistics in the SPECIAL character system.

Fallout, Fallout 2 and Fallout TacticsEdit

Modifies: the number of new skill points per level, dialogue options, and many skills.

One of the unique qualities of Fallout and Fallout 2 was the difference in gameplay caused by creating a low-Intelligence character. With a dimwitted player character, many non-player characters will simply shrug one off, while others will insult or even attack them. It is possible to complete the game as an idiot, but most side-quests are impossible to do, and character growth is limited, as is the story involvement possible - while it is possible to bumble through the main quests, almost all plot details and background information will be left missing. Furthermore, due to limited-at-best non-player character interaction, almost all side-quests are unavailable. Because of this, playing as a low Intelligence character is only recommended for experienced players looking to role-play, or as a humorous replay option.

Ways to increase IntelligenceEdit

  • In Fallout, the Brotherhood of Steel doctor in the Lost Hills can perform an operation to permanently increase Intelligence by 1, assuming it can be afforded.
  • Intelligence can be raised permanently in Fallout 2 in three ways. First, by using ACE and the yellow memory module (+1). Second, by the Hubologist zeta scan/alignment in San Francisco (which can also provide +1 Luck, though the game may need save-scumming to get a bonus rather than a penalty). The paste method is to take the Gain Intelligence Perk. The bonuses from these methods stack for a total of +3 Intelligence.
  • In both Fallout 1 and 2, Mentats can be used to temporarily raise Intelligence by 2.
  • In Fallout 2, Intelligence can be temporarily raised by 1 point by the Purchase the Kesting Special quest given by Miss Kitty in the Cat's Paw brothel.

Intelligence-based perksEdit

Perk Required Level Additional Requirements Games
Brown Noser 6 2 Charisma 5 Fallout Tactics
Comprehension 6 3 - Fallout 2, Fallout Tactics
Healer 5 3 Perception 7, Agility 6, First Aid 40% Fallout, Fallout 2, Fallout Tactics
Smooth Talker 4 3 - Fallout, Fallout 2
Survivalist 6 3 Endurance 6, Outdoorsman 40% Fallout, Fallout 2, Fallout Tactics
Swift Learner 4 3 - Fallout, Fallout 2, Fallout Tactics
Death Sense 5 4 Deathclaws only Fallout Tactics
Educated 6 6 - Fallout, Fallout 2, Fallout Tactics
Empathy 5 6 Perception 7 Fallout, Fallout 2
Rad Resistance 4 6 Endurance 6 Fallout, Fallout 2, Fallout Tactics
Sharpshooter 6 6 / 9 Perception 7 Fallout, Fallout 2, Fallout Tactics
Crazy Bomber 6 9 Traps 60%, Unavailable to deathclaws and dogs Fallout Tactics
Bonus Rate of Fire 6 9 / 15 Perception 6, Agility 7 Fallout, Fallout 2, Fallout Tactics
Road Warrior 6 12 Pilot 60%, Unavailable to deathclaws and dogs Fallout Tactics
Autodoc Lowered Hit Points <4 - Luck 2, Ride the Autodoc Rodeo Fallout 2
Autodoc Lowered Hit Points II <4 - Luck 1, Ride the Autodoc Rodeo Fallout 2
Autodoc Raised Hit Points <4 - Luck 9, Ride the Autodoc Rodeo Fallout 2
Autodoc Raised Hit Points II <4 - Luck 10, Ride the Autodoc Rodeo Fallout 2

Fallout 3Edit

Modifies: Medicine, Repair, and Science skills, as well as the number of new skill points per level.

Intelligence determines the number of skill points earned per level up. The base number of skill points gained per level is 10 + INT. Skill points gained for raised Intelligence are not retroactive for past levels, so increasing this primary stat early, if at all, is the best. Also, temporary modifiers to Intelligence (e.g. from Night Person or Button's wig) do not affect the number of skill points gained when leveling up.

Value Skill Points / Level Skill Modifiers
1 11 Medicine +2, Repair +2, Science +2
2 12 Medicine +4, Repair +4, Science +4
3 13 Medicine +6, Repair +6, Science +6
4 14 Medicine +8, Repair +8, Science +8
5 15 Medicine +10, Repair +10, Science +10
6 16 Medicine +12, Repair +12, Science +12
7 17 Medicine +14, Repair +14, Science +14
8 18 Medicine +16, Repair +16, Science +16
9 19 Medicine +18, Repair +18, Science +18
10 20 Medicine +20, Repair +20, Science +20

Intelligence-based perksEdit

Perk Requirement Level Additional Requirements
Daddy's Boy / Daddy's Girl 4 2
Gun Nut 4 2 Agility 4
Swift Learner 4 2
Comprehension 4 4
Educated 4 4
Entomologist 4 4 Science 40
Nerd Rage! 5 10 Science 50
Computer Whiz 7 18 Science 70
Warmonger 7 26

Ways to increase IntelligenceEdit



  • If the Lone Wanderer has an Intelligence below 4, Dean Dewey will call them a "special needs" child and escort them to a classroom.

Fallout: New VegasEdit

Intelligence affects skill points differently from how it did in Fallout 3. The number of skill points gained each level is based on the formula 10 + (0.5 * IN) per level, including level 1, where IN is the Courier's Intelligence. If one gets a non-whole number of skill points per level (e.g. 10.5 for INT 1) it will be saved for the next even level up (see Skill Rate).

Intelligence-based perksEdit

Perk Requirement Level Additional Requirements
Retention 5 2
Swift Learner 4 2
Comprehension 4 4
Educated 4 4
Entomologist 4 4 Survival 45
Pack Rat 5 8 Barter 70
Nerd Rage! 5 10 Science 50
Computer Whiz 7 18 Science 70
Voracious Reader Gametitle-FNV LR 7 22
Lessons Learned Gametitle-FNV LR 6 26

Ways to increase IntelligenceEdit


Intelligence in quests and explorationEdit

  • When speaking with Arcade Gannon, a Courier with an Intelligence of 3 or less can convince him to become their companion by stating "This place is really complicated and stuff. You're smart, can you help me do... stuff?"[1]
  • Having a character with Intelligence of 3 or less can grant "special" Intelligence checks. If the character's Intelligence is really low, dialog options will appear to be short and monosyllabic, with barely any sentience.
  • When first meeting Ignacio Rivas at HELIOS One, he will ask the player character what their interest in the place is. If the their Intelligence is high, they may respond with "My interest in this place is scientific." However, with a low Intelligence, the same option will be available as "I is scientistic."
  • An Intelligence of 6 is needed to tell Veronica that the Brotherhood of Steel are only hostile if one uses plasma or laser weaponry around them. Otherwise, a Courier with low intelligence can only humorously state the Brotherhood are known to shoot lasers from their eyes.
  • An Intelligence of 6 is needed to ask Arcade Gannon how he knows so much when one enters REPCONN headquarters.
  • An Intelligence of 6 is needed to ask Orris how he managed to kill 4 thugs with 3 shots during the G.I. Blues quest.
  • To convince Joe Cobb that he can be the newly (self-appointed) mayor of Goodsprings, an intelligence of 6 is required.
  • A Intelligence of 6 is required to tell Boone that snipers work in teams as a dialogue option at the end of One for My Baby.
  • Gametitle-FNV OWB An Intelligence of 6 is needed for Dr. Mobius to reveal that they are still planning how to save themselves.
  • A character with an Intelligence of 6 or lower will admit they don't know what a fish is during a conversation with Cass. With an Intelligence of 7 or higher the Courier will ask Cass in return if she knows it.[2]
  • An Intelligence of 7 or a Speech of 70 allows the Courier to talk Alice Hostetler down from killing her mother in the quest Someone to Watch Over Me.
  • An Intelligence of 8 is needed to trick Silus into thinking the Courier is an agent of Caesar's Legion on a mission to kill him. Silus will take the bluff and inform the Courier about Caesar's brain tumor and indirectly about Ronald Curtis.
  • Gametitle-FNV OWB An Intelligence of 8 is needed to reveal the fact that Dr. Mobius scattered the personality chips across Big MT.
  • Gametitle-FNV OWB An Intelligence of 7 and a subsequent value of 9 or having the Math Wrath Perk is required to resolve Dr. 0's naming issue.
  • During the quest, Come Fly With Me If your Intelligence is below 4, you can also try randomly mashing the buttons on the control panel. Watch the cut scene as the rockets take off from the opened launch hangar. You should see a notification that your reputation in Novac is improved.

Level names and statisticsEdit

Value Name Skill Points Skill Modifiers
1 Sub-brick 10.5 Medicine/Repair/Science +2
2 Vegetable 11 Medicine/Repair/Science +4
3 Cretin 11.5 Medicine/Repair/Science +6
4 Knucklehead 12 Medicine/Repair/Science +8
5 Knowledgeable 12.5 Medicine/Repair/Science +10
6 Gifted 13 Medicine/Repair/Science +12
7 Smartypants 13.5 Medicine/Repair/Science +14
8 Know-it-all 14 Medicine/Repair/Science +16
9 Genius 14.5 Medicine/Repair/Science +18
10 Omniscient 15 Medicine/Repair/Science +20

Fallout 4Edit

Intelligence is the measure of your overall mental acuity, and affects the number of experience points earned.

Unlike in previous games, Intelligence has no effect on skills, since Fallout 4 lacks a separate set of scores for your skills. Instead, a higher Intelligence—in addition to unlocking higher perks in the Intelligence category—will increase the amount of experience your character earns from all sources.

The experience multiplier linearly increases from 103% (1 Intelligence) to 130% (10 Intelligence).[3] In other words, it increases XP gains by 3% per INT. It continues increasing if Intelligence is brought higher than 10. In math terms:

$ {\it XP}_{\rm Final} = {\it XP}_{\rm Base}\times \left(1 + \frac{{\it Intelligence} \times 3}{100}\right) $[4]

A higher Intelligence also reduces the number of words that are displayed while hacking a terminal; for example, at an Intelligence of 10 or higher with a Science bobblehead, it almost becomes trivial to brute-force most hacking sessions.

Ways to increase IntelligenceEdit


Ways to decrease IntelligenceEdit


Intelligence in quests and explorationEdit

  • The Last Voyage of the U.S.S. Constitution has multiple intelligence checks that can speed up progression through the quest. Instead of replacing components, the player can repair them instead. This strategy applies to the replacement of the wires (requiring an intelligence of 5) and radio antenna (with a score of 9 int).
  • When romancing Magnolia, she may compliment the character's intelligence if the score is his or her highest SPECIAL attribute.

Fallout 76Edit

Intelligence is a measure of your overall mental acuity, and effects your ability to hack terminals, the condition and durability of items that you craft, and the return you get from scrapping.

Fallout ShelterEdit

Intelligence affects how efficient a dweller is while working in the medbay and science lab facilities. A dweller's Intelligence can be increased by assigning them to the classroom.

Fallout: The Board GameEdit

Unlike other games, Intelligence is not treated as a variable ranging from 1 to 10, but instead as a token that can be obtained at the start or when leveling up. A player character with the Intelligence token gets free rerolls during certain tests, as well as during fights if equipped with an Intelligence-based weapon. They can also recruit certain companions from the shop.

The Brotherhood Outcast player character always begins the game with Intelligence. Any player character wearing the lab coat gains one hit during an Intelligence test. During any Intelligence test, Mentats can be used to gain one free hit.

Intelligence-based perksEdit

Intelligence-based weaponsEdit

Companions requiring IntelligenceEdit

Low Intelligence charactersEdit

Fallout 1 & 2Edit

When the player character in Fallout and Fallout 2 has less than 4 Intelligence, the biggest change in gameplay is undoubtedly the dialogue. Upon reaching Shady Sands, the villagers take pity on the Vault Dweller, and Aradesh will simply shrug them off. The best they can speak is half-word sentences or gibberish.

The real downside, though, is the nigh impossibility to do about 90% of the side quests. No one will talk to a moron or even give them the time of day.

In Fallout 2, the Chosen One may meet Torr, the "town simpleton of Klamath," who would normally give them a quest to help protect his brahmin against "the evil bugmen." If the player character has low Intelligence, however, he will appear to be highly intelligent as if being stupid has a culture and language of its own. Two flat-headed people can have a complete, thought-provoking, and fully articulated conversation between them.

Another person one may have an "intelligent" conversation with in Fallout 2 is AHS-9, who becomes able to understand what the Chosen One tries to say after the alignment, and gives the quest to kill the Shi Emperor.

When talking to Algernon in the basement of New Reno Arms, the Chosen One can start a childhood "cop and robbers" type dialog in which they accidentally "shoot" and kill him.

A character with a low Intelligence is unable to gamble. When they observe a roulette table or a slot machine, the character will respond to it as a fun toy or an interactive character, respectively. Visiting a craps table will result in a dumb Chosen One commenting to the dealer that they "play craps in pants".

Fallout 3Edit

In Fallout 3, there are conversation situations where characters with low Intelligence are granted other dialogue options, often relating to their low intellect. However, these options are few and far between, unlike the other Fallout games where one could play the entire game as a person without Intelligence. One instance is in Roosevelt Academy, where if the Lone Wanderer activates Dean Dewey while having an Intelligence below 4, he will deem them a "special needs" child, and escort them to a "proper room."

Fallout: New VegasEdit

In addition to alternative Intelligence checks, low Intelligence changes some dialog options when speaking to vendors and non-player characters. For example, when speaking to Miguel at Miguel's Pawn Shop, the option to start trading is "Me buy things," and when speaking with Dr. Usanagi at the New Vegas medical clinic, after she gives the Courier the initial description about implants they get the dialogue option "You sell plants, too?", which will cause her to re-explain the implants and suggest [the player character] take the implant to make them smarter. If taking her up on this deal, she will state that she thinks the Courier "could really benefit from it," and offer the implant at a discount.

In place of the gibberish of past games, however, the player character will simply not completely understand a conversation, confuse what someone is saying with something else entirely, or not understand what situation they are currently in. In the REPCONN headquarters, for example, a character with an IN of < 3 can bypass a robot that demands a password by saying "ICE CREAM!" Normally, a Luck of at least 7 would be needed to guess this.

Low-intelligence characters attempting to do the quest That Lucky Old Sun will be granted several unique and highly entertaining dialog options when conversing with Fantastic and Ignacio Rivas. An example is when informed about the hostilities between the Followers and the NCR, the Courier can ask, "Do Flowers and NCR bear play together?"

When first speaking to Ranger Milo he will inform the Courier that some "Legion snakes" are held up in Nelson, to which they can respond "Snakes are small. Why don't you just use a gun or whatever to shoot them." He will then call them a "special folk," and explain that they are not really snakes but "like snakes."

While helping Argyll in Nellis medical station while doing the quest Volare!, the Courier is given an option to "CHOP CHOP CHOP!" instead of giving him treatment. Ironically, the Courier actually saves the patient and Argyll comments on it, saying it was "dumb luck."

Notable quotesEdit

  • "Me Shoulder" – a ditzy Vault Dweller
  • "I don't care if you were dropped on your head as a kid. No guns in the city limits." – NCR gate guard.
  • "Glug glug glug glug glug glug!" – another Vault Dweller
  • "*Snfff* You big meenie... *snff*... me go sumplace 'n have partee wiff clowns... *snfff*... and ice cream... and kake... and me no invit meen peuple like YOU!" – a childish Chosen One
  • "Most people have evil spirits. You? You have stupid spirits. Go see shaman, get hole in head... Big hole... Very big... Huge." – Sulik
  • "Hep Torr hep moo-moo. (Yes, of course I'll help you fend off the predation of your family's brahmin by these nefarious bugmen.)" – Chosen One to Torr
  • "Me help shoulders make shinies warm." – A Courier
  • "I IS SCIENTISTIC!" – another Courier with improper language skills
  • "What are Flowers of Pock-lips?" – a Courier misunderstanding
  • "Ooh Shiney Robot" – the Lone Wanderer
  • "ICE CREAM!" – Courier with Intelligence 1 or 2 at REPCONN headquarters
  • "Me pet aminals" – the Courier
  • "I no hurt anyone" – the Courier
  • "Where I send shiny juice?" – the Courier
  • "Me take you job cause me is smarter" – the Courier
  • "You no ask." – the Courier
  • "Very well. Let me put this into terms you'll understand. Brain: Smart. Heart: Stupid. Spine: Very stupid. You: Exceptionally stupid." – the Courier's brain to a low intelligence Courier
  • "Not 'ha ha' funny, you moron. Funny as in suspicious." – Eddie to a dumb Courier.
  • "Hmm. Wow. You sound like you really do need some help. Look, I can help you out, but you can't do anything stu- <ahem> I mean, you can't... help bad people, who want to hurt the locals in Freeside. If you do, I'll leave. Does that make sense?" – Arcade Gannon
  • "Pizza/Warm" – the Courier misinterpreting "Peace" and "War" respectively


In Fallout: New Vegas, if the Courier's Intelligence stat is the most extreme (highest or lowest), Doc Mitchell will either compliment saying "maybe them bullets done your brain some good." (for highest) or apologize, stating he fixed up the Courier's head the best he could. (For lowest).



Fallout 4 S.P.E.C.I.A.L

Fallout 4 S.P.E.C.I.A.L. Video Series - Intelligence

Fallout 4 Intelligence promotional video