All creatures—characters and monsters—have six abilities that measure physical and mental characteristics, as shown on the Ability Descriptions table.
| Ability | Score Measures ... |
|---|---|
| Strength | Physical might |
| Dexterity | Agility, reflexes, and balance |
| Constitution | Health and stamina |
| Intelligence | Reasoning and memory |
| Wisdom | Perceptiveness and mental fortitude |
| Charisma | Confidence, poise, and charm |
Each ability has a score from 1 to 20, although some monsters have a score as high as 30. The score represents the magnitude of an ability. The Ability Scores table summarizes what the scores mean.
| Score | Meaning |
|---|---|
| 1 | This is the lowest a score can normally go. If an effect reduces a score to 0, that effect explains what happens. |
| 2–9 | This represents a weak capability. |
| 10–11 | This represents the human average. |
| 12–19 | This represents a strong capability. |
| 20 | This is the highest an adventurer’s score can go unless a feature says otherwise. |
| 21–29 | This represents an extraordinary capability. |
| 30 | This is the highest a score can go. |
Each ability has a modifier that you apply whenever you make a D20 Test with that ability (explained in “D20 Tests”). An ability modifier is derived from its score, as shown in the Ability Modifiers table.
| Score | Modifier |
|---|---|
| 1 | −5 |
| 2–3 | −4 |
| 4–5 | −3 |
| 6–7 | −2 |
| 8–9 | −1 |
| 10–11 | +0 |
| 12–13 | +1 |
| 14–15 | +2 |
| 16–17 | +3 |
| 18–19 | +4 |
| 20–21 | +5 |
| 22–23 | +6 |
| 24–25 | +7 |
| 26–27 | +8 |
| 28–29 | +9 |
| 30 | +10 |
Round Down
Whenever you divide or multiply a number in the game, round down if you end up with a fraction, even if the fraction is one-half or greater. Some rules make an exception and tell you to round up.