Skills
A Complete Reference
Everything you need to understand how skills work — with real numbers, worked examples, and the math laid bare.
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 → FAILURE
Roll 17 or 18 → AUTOMATIC FAILURE (regardless of skill level)
Roll 3 or 4 → CRITICAL SUCCESS (regardless of skill level)
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.
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.
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.
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.
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−3 | — | — | — | 1 pt |
| Attribute−2 | — | — | 1 pt | 2 pts |
| Attribute−1 | — | 1 pt | 2 pts | 4 pts |
| Attribute+0 | 1 pt | 2 pts | 4 pts | 8 pts |
| Attribute+1 | 2 pts | 4 pts | 8 pts | 12 pts |
| Attribute+2 | 4 pts | 8 pts | 12 pts | 16 pts |
| Attribute+3 | 8 pts | 12 pts | 16 pts | 20 pts |
| Attribute+4 | 12 pts | 16 pts | 20 pts | 24 pts |
| Attribute+5 | 16 pts | 20 pts | 24 pts | 28 pts |
| Each extra +1 | +4 pts | +4 pts | +4 pts | +4 pts |
Your DX is 12. You want Swimming (DX/Easy) at DX+1 = 13. Cost: 2 points.
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.
Your IQ is 11. You want Surgery (IQ/Hard) at skill 13. That's IQ+2. Find row "Attribute+2," column "Hard": 12 points.
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.
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 |
|---|---|---|---|
| 8 | 26% | Struggling — worse than 1-in-4 | |
| 9 | 38% | Below average | |
| 10 | 50% | Coin flip | |
| 11 | 63% | More likely to succeed than fail | |
| 12 | 74% | Solid competence | |
| 13 | 84% | Reliable under pressure | |
| 14 | 91% | Expert — rarely fails | |
| 15 | 95% | Near-professional mastery | |
| 16+ | 98% | Capped here — 17 & 18 always fail |
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.
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
| Tier | Skill Range | Who This Represents |
|---|---|---|
| Ordinary People | 8 – 13 | 20–40 pts spread across ~12 skills. Trade skills near 12–13; half-forgotten hobbies near 8–9. |
| Experts | 14 – 18 | Rarely fail normal tasks. Extra levels are insurance against tough situational penalties. |
| Masters | 20 – 25 | Sweet spot for a primary skill. Better to branch into subsidiary skills than stack beyond 25. |
| Excessive | 25+ | Diminishing returns. A Karate-25 master + Acrobatics + Judo beats Karate-30 + nothing. |
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.
Average skill default: Attribute − 5
Hard skill default: Attribute − 6
Very Hard and some others: No default — cannot attempt without training
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.
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.
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.
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.
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
| Rule | Detail |
|---|---|
| Rule of 20 | If your attribute exceeds 20, treat it as 20 for calculating defaults. Superhuman characters get good defaults, not absurd ones. |
| Cultural Limits | You can only default to skills that exist in your society. A medieval knight has no default for Scuba — he's never encountered the concept. |
Relative Skill Level
This separates natural talent (your attribute) from training and experience (your relative level). Two characters can have identical skill levels for very different reasons.
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.
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 TL | Penalty |
|---|---|
| 4+ TLs ahead | Impossible |
| 3 TLs ahead | −15 |
| 2 TLs ahead | −10 |
| 1 TL ahead | −5 |
| Matching TL | No penalty |
| 1 TL behind | −1 |
| 2 TLs behind | −3 |
| 3 TLs behind | −5 |
| 4 TLs behind | −7 |
| Each further TL behind | −2 more |
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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 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.
Running Example: Mira
Let's tie everything together with a single character: Mira, a DX 12 / IQ 11 swordswoman and part-time field surgeon.
| Skill | Type | Points | Level | Success | Notes |
|---|---|---|---|---|---|
| Shortsword | DX/Average | 4 pts | 13 | 84% | DX+1 |
| Broadsword | DX/Average | 0 pts | 11 | 63% | Free default from Shortsword−2 |
| Surgery/TL8 | IQ/Hard | 12 pts | 13 | 84% | Drops to skill 3 at TL10 gear (−10) |
| Chemistry (Analytical) | IQ/Average* | 2 pts | 11 | 63% | Outside specialty: rolls at 9 (38%) |
| Guns (Pistol) | DX/Easy | 1 pt | 12 | 74% | 2 free familiarities; −2 with unknown models |
*Chemistry (Analytical) is IQ/Hard normally, but the optional specialty reduces it to IQ/Average.
If Mira raises DX from 12 to 13, her Shortsword automatically jumps to 14 and her Guns (Pistol) to 13 — both for free, as part of the attribute improvement. Her Broadsword default also rises to 12. One investment, multiple gains.