Chapter Four · GURPS Basic Set

Skills
A Complete Reference

Everything you need to understand how skills work — with real numbers, worked examples, and the math laid bare.

01

What Is a Skill?

A skill is any specific area of knowledge or ability — swordfighting, surgery, chemistry, piloting, a death spell. Every skill is separate, though related skills often help each other. You start with some skills and can learn more through training.

Each skill has a skill level — a single number. When you attempt to use a skill, you or the GM roll 3d (three six-sided dice). If the result is equal to or under your skill level, you succeed. If it exceeds your skill level, you fail.

Roll 3d ≤ skill level → SUCCESS
Roll 3d > skill level → FAILURE
Roll 17 or 18 → AUTOMATIC FAILURE (regardless of skill level)
Roll 3 or 4 → CRITICAL SUCCESS (regardless of skill level)
Example

Your character has Shortsword-13. You roll 3d and get 9 — since 9 ≤ 13, you succeed. Later you roll 15 — since 15 > 13, you fail. Even if your skill were Shortsword-20, rolling a 17 or 18 would still be an automatic failure.

02

Controlling Attributes

Every skill is anchored to one of your core attributes. This is called the controlling attribute. Your skill level is calculated relative to that attribute's score — a high attribute gives you a head start on every skill linked to it.

ST · Strength
Brawn
Very rare as a direct skill base. ST more often determines power with DX-based skills.
DX · Dexterity
Coordination
Athletic skills, all combat skills, most vehicle operation. The widest category.
IQ · Intelligence
Knowledge
Academic, artistic, social, and all magic skills. Creativity and reasoning required.
HT · Health
Fitness
Physical endurance skills — activities governed by posture, hygiene, or lung capacity.
Per · Perception
Awareness
Spotting subtle differences. Tracking, searching, detecting hidden objects and clues.
Will
Mental Focus
Resisting mental attacks, entering altered states, focusing inner strength.
Key Tip

If your character concept leans heavily on one attribute, invest there first. Raising DX by 1 automatically raises every DX-based skill you own — far more efficient than buying each skill up individually.

From GURPS For Dummies — Attribute First, Skills Second

GURPS For Dummies recommends considering whether to raise the controlling attribute rather than buying each skill individually. If you find yourself putting 2+ points into ten or more skills based on the same attribute, it may be cheaper to raise that attribute by 1 and lower your per-skill investment accordingly.

This matters most for DX-based fighters: a single +1 to DX improves every weapon skill, every athletic skill, and every evasion roll simultaneously. A scholar stacking IQ gets the same multiplier effect across all knowledge and social skills.

03

Difficulty Levels

Not all skills are equally hard to learn. GURPS assigns one of four difficulty levels to every skill, which directly affects how many character points you must spend to reach a given level.

Difficulty Description Example Skills
Easy Second nature to most people; picked up quickly Swimming, Climbing (basic), Thrown Weapon
Average Most combat, social, and everyday job skills Shortsword, Guns, Driving, Persuasion
Hard Requires intensive, formal study over years Surgery, Lockpicking, most magic spells
Very Hard Enormous scope, alien, or deliberately secret Fundamental sciences, powerful spells, secret arts

As you'll see in the next section, harder difficulty means you pay substantially more points to achieve the same skill level relative to your controlling attribute.

From GURPS For Dummies — Choosing Skill Difficulty Wisely

GURPS For Dummies points out that generalist characters tend to have many skills at moderate levels (12–14), while specialist characters have fewer skills but at higher levels (14–16). Difficulty level is the key constraint: Very Hard skills are brutally expensive to raise, so specialists who invest heavily in one Very Hard skill often leave little room for anything else.

A practical tip from the book: identify one or two skills as your character's primary focus and push those to an extremely high level (17+). For everything else, a 1–2 point investment at a moderate level is usually enough.

04

Buying Skills: The Cost Table

Skill levels are measured relative to your controlling attribute. "Attribute+0" means your skill equals the attribute exactly. "Attribute+2" means your skill is 2 higher. The cost depends entirely on this relative difference and the skill's difficulty.

Relative Level Easy Average Hard Very Hard
Attribute−31 pt
Attribute−21 pt2 pts
Attribute−11 pt2 pts4 pts
Attribute+01 pt2 pts4 pts8 pts
Attribute+12 pts4 pts8 pts12 pts
Attribute+24 pts8 pts12 pts16 pts
Attribute+38 pts12 pts16 pts20 pts
Attribute+412 pts16 pts20 pts24 pts
Attribute+516 pts20 pts24 pts28 pts
Each extra +1+4 pts+4 pts+4 pts+4 pts
Example A — Easy Skill

Your DX is 12. You want Swimming (DX/Easy) at DX+1 = 13. Cost: 2 points.

Example B — Average Skill

Your DX is 14. You want Shortsword (DX/Average) at skill level 17. That's DX+3 (14+3=17). Find row "Attribute+3," column "Average": 12 points.

Example C — Hard Skill

Your IQ is 11. You want Surgery (IQ/Hard) at skill 13. That's IQ+2. Find row "Attribute+2," column "Hard": 12 points.

Pattern to Notice

At Attribute+2, the same relative level costs 4 pts (Easy), 8 pts (Average), 12 pts (Hard), or 16 pts (Very Hard). Difficulty doubles the price at every tier.

GURPS for Beginners — Point Costs in Play

The cost table can feel abstract. Think of it this way: 1 point buys "I took a class once." 4 points buys "I trained seriously." 8+ points buys "This is my career."

A warrior spending 8 points on Broadsword gets DX+2 — genuinely skilled. Spending those same 8 points across four Easy skills at 2 pts each gets you four competent abilities. Concentration or breadth: your choice.

05

What Do Skill Levels Actually Mean?

Rolling 3d produces a bell-curve distribution. Here's exactly what each skill level translates to in terms of your raw chance of success — before any situational modifiers:

Skill Level Chance of Success Visual What It Means
826%
Struggling — worse than 1-in-4
938%
Below average
1050%
Coin flip
1163%
More likely to succeed than fail
1274%
Solid competence
1384%
Reliable under pressure
1491%
Expert — rarely fails
1595%
Near-professional mastery
16+98%
Capped here — 17 & 18 always fail
The Real Value of High Skills

Going from skill 15 to 16 adds only ~3% to your success rate. The true value of high skills is absorbing penalties. A difficult lock gives −6 to skill. With Lockpicking-15, you're at effective skill 9 (38%). With Lockpicking-23, you're still at effective skill 17 (98%).

Base Skill vs. Effective Skill

Your printed skill level is your base skill — your odds at an average adventuring task. The GM applies modifiers for task difficulty, conditions, and stress. Your effective skill is the number you actually roll against.

Example

A pilot has Piloting-12 (base: 74% success). For routine fair-weather flying: GM gives +4 → effective skill 16, 98% success. During a storm with engine failure: GM imposes −4 → effective skill 8, 26% success. The base skill never changed — only the situation did.

Choosing Your Level: A Practical Guide

TierSkill RangeWho This Represents
Ordinary People8 – 1320–40 pts spread across ~12 skills. Trade skills near 12–13; half-forgotten hobbies near 8–9.
Experts14 – 18Rarely fail normal tasks. Extra levels are insurance against tough situational penalties.
Masters20 – 25Sweet spot for a primary skill. Better to branch into subsidiary skills than stack beyond 25.
Excessive25+Diminishing returns. A Karate-25 master + Acrobatics + Judo beats Karate-30 + nothing.
From GURPS For Dummies — Why High Skills Absorb Penalties

The real reason to push a primary skill high is not the raw success rate — it is penalty absorption. A difficult task, bad lighting, or rushed conditions might impose −4 to −8 on a roll. A character with Broadsword-12 drops to an effective skill of 4 under a −8 penalty. A character with Broadsword-20 drops to 12 — still solid.

GURPS For Dummies frames this clearly: once a skill is above 15, extra levels matter less for routine use and more as a buffer against the worst situations your GM can throw at you.

06

Skill Defaults: Using Skills Without Training

Most skills have a default level — how well you perform with zero training, using nothing but common sense and background knowledge.

Easy skill default: Attribute − 4
Average skill default: Attribute − 5
Hard skill default: Attribute − 6
Very Hard and some others: No default — cannot attempt without training
Example — Broadsword Default

Broadsword is DX/Average. Your DX is 11. Untrained default = 11 − 5 = 6. You need to roll 6 or less on 3d to hit — about a 9% chance. You can swing a sword, but you're dangerous mostly to yourself.

No Default Skills

Skills like Alchemy, Hypnotism, and Karate have no default at all — you cannot attempt them without at least 1 point spent. Even a plausible default gives you none of the special skill benefits (combat bonuses, improved damage, etc.) unless you've invested at least 1 character point.

Defaulting to Another Skill

Some skills default to a related skill rather than (or in addition to) an attribute. Training in one area partially transfers to similar disciplines.

Example — Cross-Skill Default

Broadsword defaults to Shortsword−2. If you have Shortsword-13, you automatically have Broadsword-11 for free — no points spent. The two weapons are similar enough that training transfers.

Improving From a Default

If your default already puts you at a level that would have cost points, you only pay the difference to improve further — not the full cost from scratch.

Example — Cheapening Improvement

Your DX is 12 and Shortsword is 13 (DX+1). Your Broadsword default is 11 (Shortsword−2). Broadsword-11 = DX−1, which normally costs 1 point. The next level (DX+0 = 12) costs 2 points. Since you're already effectively at the 1-point threshold via your default, you only pay 1 point to go from 11 → 12, not 2.

Double Defaults Don't Chain

If Skill A defaults to Skill B−5, and Skill B defaults to IQ−5, Skill A does not default to IQ−10. You can only use a default from a skill you actually possess — not a skill someone else holds at default.

Additional Default Rules

RuleDetail
Rule of 20If your attribute exceeds 20, treat it as 20 for calculating defaults. Superhuman characters get good defaults, not absurd ones.
Cultural LimitsYou can only default to skills that exist in your society. A medieval knight has no default for Scuba — he's never encountered the concept.
From GURPS For Dummies — Defaults Explained

A default is your "untrained attempt." Anyone with a related skill or a high enough attribute can try — but at a penalty. The key rule: you can only default if the task is not too complex. Surgery never has a default; picking a simple lock might.

Defaults also let skills feed into each other. High Broadsword gives you a free Shortsword default, which gives a Knife default. One investment, a whole family of competence.

07

Relative Skill Level

Relative Skill Level = Skill Level − Controlling Attribute

This separates natural talent (your attribute) from training and experience (your relative level). Two characters can have identical skill levels for very different reasons.

Example — Same Skill, Different Stories

Both warriors have Shortsword-17. They're equally dangerous.

Warrior A: DX 17. Relative level = 17 − 17 = +0. Naturally gifted — barely needed to train.

Warrior B: DX 10. Relative level = 17 − 10 = +7. Grinded for years to reach the same result through sheer dedication.

In a fight they're equal. But if the GM wants to test experience specifically — say, recognizing a rare technique — Warrior B rolls against 10+7=17, Warrior A against 10+0=10. Training wins.

08

Technological Skills

Skills tied to a specific Tech Level (TL) are written with "/TL" — e.g., Surgery/TL9. Surgery/TL4 (saw off a limb) and Surgery/TL9 (graft a cloned replacement arm) share a name but represent entirely different bodies of knowledge.

You learn TL skills at your personal TL. You can learn lower-TL skills freely at character creation. Higher-TL skills can only be learned in play, with a teacher — and IQ-based ones require you to raise your personal TL first.

IQ-Based TL Skills: Knowledge Penalties

These represent genuine understanding of the science and engineering of a specific era. Mismatched equipment is punishing:

Equipment TL vs. Skill TLPenalty
4+ TLs aheadImpossible
3 TLs ahead−15
2 TLs ahead−10
1 TL ahead−5
Matching TLNo penalty
1 TL behind−1
2 TLs behind−3
3 TLs behind−5
4 TLs behind−7
Each further TL behind−2 more
Example — TL Mismatch

A TL8 engineer (modern day) tries to diagnose a TL10 starship computer. That's 2 TLs ahead: −10 penalty. If her Computer skill is 15, effective skill = 5 — barely above guessing.

Non-IQ TL Skills: Flat −1 per TL

These skills involve operating equipment rather than understanding it. A TL5 gunslinger picking up a TL7 revolver takes a flat −1 per TL of difference, in either direction.

Example — Gun Handling Across TLs

A TL5 gunman fires a TL7 revolver: −2 (2 TLs difference). A TL7 cop fires a TL5 revolver: also −2. The old mechanisms feel unfamiliar too — the penalty runs both directions.

09

Specialties

Some skill entries represent a category of closely related skills. When you learn one, you must choose a specialty. Each specialty is a separate skill — you can hold several but must pay for each.

Example — Required Specialties

Survival (Arctic), Survival (Desert), and Survival (Jungle) all use the "Survival" heading but are different skills entirely. You write them with the specialty in parentheses.

Optional Specialties

For IQ-based Average-or-harder skills, you may choose to specialize even when it isn't required. Doing so lets you learn that specialty as if it were one difficulty tier easier. The tradeoff: your general skill defaults to your specialty at −2, and you suffer that penalty for anything outside your narrow focus.

Example — Optional Specialty

Chemistry is IQ/Hard and requires no specialty. You specialize in Chemistry (Analytical), learned as IQ/Average — cheaper to buy up. If asked a general chemistry question outside your subfield, you roll Chemistry (Analytical)−2. Metallurgy, which normally defaults to Chemistry−5, would default to Chemistry (Analytical)−7.

From GURPS For Dummies — Specialties as Investment Strategy

GURPS For Dummies explicitly recommends tracking skills with required specializations as separate entries on your sheet — for example, Armory (Small Arms) and Armory (Melee Weapons) are two distinct skills. This matters when calculating point costs and when trading up from a default.

Optional specialties offer a real trade-off: you pay fewer points to reach a high level in your chosen niche, but your general knowledge in that skill family takes a −2 hit. Worth it for scholars and craftsmen with a narrow professional focus; less useful for explorers who need breadth.

10

Prerequisites

Some advanced skills require you to have another skill first. The prerequisite must be purchased with at least 1 character point — a default doesn't count. Some prerequisites demand a minimum skill level. A few require specific advantages: if you can't acquire the advantage at all, you can never learn the skill.

Example

To learn a high-level magic spell, you might need its prerequisite spell at skill 15 or better. To learn Karate, you need the "Trained By A Master" advantage or access to an appropriate martial arts teacher in play.

11

Improving Skills Over Time

You improve skills by spending earned bonus points from adventuring, or by dedicating in-game time to study. Either way, you pay the difference between your current skill's point cost and the cost of the target level — never the full price from scratch.

Example — Upgrading a Skill

Your Shortsword is at 13 (DX+1 = 4 pts for Average). You want to raise it to 14 (DX+2 = 8 pts). You pay 8 − 4 = 4 points, not 8 from scratch.

Free Increases Via Attributes

If you raise your DX by 1, every DX-based skill you own automatically rises by 1 at no extra cost. Raising DX from 12 to 13 might simultaneously improve a dozen skills — often the most efficient investment in the game.

Practical Advice — How to Spend Skill Points

New GURPS players often spread points too thin. The recommendation from experienced players: put 4+ points into your signature skills and leave the rest as defaults or 1-point buys. A fighter with Broadsword-14 (8 pts) beats four fighters each with a different combat skill at 11 (2 pts each).

For non-combat characters: one deep specialty (8+ points) plus a spread of 1-2 point supporting skills is the sweet spot. This reflects real learning — people master one thing and dabble in everything else.

12

Familiarity

Any skill used to operate equipment takes a −2 penalty when you use an unfamiliar make or model, unless the skill description says otherwise. After 8 hours of practice, you're considered familiar.

Example

You're trained on a laser pistol (one specific model). You pick up a blaster pistol — same general skill (Beam Weapons), but different hardware. You're at −2 until you've spent 8 hours with it. After that, no penalty.

Starting Familiarities

Starting characters get 2 free familiarities for every point spent on a skill. Spend 4 points on Guns (Pistol)? You can be familiar with up to 8 handgun models from the start. If you accumulate 6+ familiarities with a skill type, the GM may rule you're already comfortable with any similar new item you encounter.

From GURPS For Dummies — Track Familiarities During Creation

GURPS For Dummies explicitly recommends making a note of your starting familiarities during character creation, not later. For each skill that requires equipment (cars, guns, vehicles, tools), mark which two models you are familiar with per point invested. This avoids mid-session arguments about whether your character has used a particular weapon before.

It also suggests confirming with your GM upfront whether broad familiarity (6+ models in a skill) earns you a blanket exception for that skill type — some GMs grant this automatically, others track it strictly.

13

Ch.4 Example Sheets

After Ch.4, each character has spent their skill points. Aldric focuses on scholarly and arcane skills. Mira invests in combat and scout skills. Vora takes pure combat — every point into hitting hard and surviving.

Aldric Vane 150 pts total
Scholar and aspiring mage. High IQ, low physical stats. Skills lean heavily academic — building the foundation for magic in Ch.5.
Basic Attributes
ST9−10 pts
DX1120 pts
IQ1480 pts
HT1110 pts
Advantages (Ch1–Ch2)
Eidetic Memory [5] Lightning Calculator [2]
Disadvantages (Ch1–Ch3)
Curious (12) [−5] Absent-Mindedness [−15] Pacifism: Reluctant Killer [−5]
Skills (Ch4 completed)
Thaumatology-16 [8] Research-15 [4] Occultism-15 [4] Staff-11 [2] Writing-14 [2] Hiking-11 [2]
Magic → Ch.5 adds Aldric's Magery and spell list — the biggest investment of his build. Ch 5 →
Point Budget — 150 total
Attributes: 100 · Advantages: 7 · Disadvantages: −25 · Skills: 22 Remaining: 46 pts (reserved for Ch5 Magery + spells)
Ch.4 Skills spend
22 / 150 pts
Mira Ashfeld 150 pts total
Warrior and scout. Former city guard. High DX and IQ let her excel in combat, stealth, and social skills — a versatile fighter with street smarts.
Basic Attributes
ST1220 pts
DX1480 pts
IQ1240 pts
HT1330 pts
Advantages (Ch1–Ch2)
Combat Reflexes [15] High Pain Threshold [10] Per +2 [10]
Disadvantages (Ch1–Ch3)
Duty (City Guard) [−10] Sense of Duty (Party) [−5] Code of Honor [−10]
Skills (Ch4 completed)
Broadsword-16 [8] Shield-15 [2] Stealth-15 [4] Streetwise-13 [2] First Aid-13 [2] Crossbow-15 [4]
Magic → Mira is not a mage. Ch.5 adds no changes. Her budget is held for Ch.6+. Ch 5 →
Point Budget — 150 total
Attributes: 170 · Advantages: 35 · Disadvantages: −25 · Skills: 22 Ch.4 spend: 22 pts skills · Full budget resolved in Ch.5+
Ch.4 Skills spend
22 / 150 pts
Vora 150 pts total
Berserker raider. Pure combat — maximum ST and HT, brute-force fighter. Every point goes into raw power and combat skills. Budget fully spent after Ch.4.
Basic Attributes
ST1660 pts
DX1240 pts
IQ8−40 pts
HT1440 pts
Advantages (Ch1–Ch2)
Very Fit [15] High Pain Threshold [10] Hard to Kill 2 [4] Fearlessness 2 [4]
Disadvantages (Ch1–Ch3)
Berserk [−10] Bad Temper [−10] Impulsiveness [−10] Struggling Wealth [−10] Social Stigma: Savage [−5] Illiteracy [−3] Quirks ×2 [−2]
Skills (Ch4 completed)
Axe/Mace-14 [8] Brawling-13 [2] Shield-13 [2] Thrown Weapon-13 [1] Swimming-15 [1] Survival-9 [4] Intimidation-10 [4]
Complete → Vora's build is fully spent after Ch.4. No magic, no psionics — pure fighter. Ch 5 →
Point Budget — 150 total
Attributes: 100 · Secondary: 9 · Advantages: 33 · Disadvantages: −50 · Skills: 22 Total: 114 pts spent · 36 pts unspent — remaining for Ch.6+
Ch.4 Skills spend
22 / 150 pts
Skill Points Compared

Aldric and Mira both spend ~22 points on skills but land in completely different places. Aldric concentrates on three scholarly skills. Mira spreads across six combat and utility skills. Vora puts everything into combat efficiency — seven skills, all physical.

14

Chapter Quiz

A randomised draw from a bank of 25 questions covering every concept in this chapter — controlling attributes, difficulty levels, the cost table, skill defaults, relative skill level, specialties, TL skills, familiarity, prerequisites, and improvement. Ten questions per round, infinite rounds.

Knowledge Check
1 / 10