I put together a New Video discussing Proficiency Bonus in Pathfinder Second Edition, citing page numbers from the Core Rulebook for your reference and as a basis for the conversation. Proficiency gives you a bonus that’s added when determining the following modifiers and statistics: AC, Attack Rolls, Perception, Saving Throws, Skills, and the Effectiveness of Spells.
Please share your comments and rules savvy as everyone is reading the newly released Core Rulebook and gleaning out our understanding of the system! I come from an old school AD&D background so learning the new rules and trying to consolidate them into subjects for others is part of the fun.
Pathfinder Core Rulebook (Second Edition) © 2019, Paizo Inc.; Designers: Logan Bonner, Jason Bulmahn,Stephen Radney-MacFarland, and Mark Seifter.
The words Proficiency Bonus appears 82 times in the CRB.
What is a Proficiency Bonus?
“Proficiency is a simple way of assessing your character’s general level of training and aptitude for a given task. It is broken into five different ranks: untrained, trained, expert, master, and legendary. Each rank grants a different proficiency bonus. If you’re untrained at a statistic, your proficiency bonus is +0—you must rely solely on the raw potential of your ability modifier. If your proficiency rank for a statistic is trained, expert, master, and legendary, your bonus equals your character’s level plus another number based on the rank (2, 4, 6, and 8, respectively). Proficiency ranks are part of almost every statistic in the game” (10).
Proficiency Rank Proficiency Bonus (Level+Rank)
Trained Your level + 2
Expert Your level + 4
Master Your level + 6
Legendary Your level + 8
“Proficiency is a system that measures a character’s aptitude at a specific task or quality, and it has five ranks: untrained,trained, expert, master, and legendary. If you’re untrained, your proficiency bonus is +0. If you’re trained, expert, master, or legendary, your proficiency bonus equals your level plus 2, 4, 6, or 8, respectively” (13).
“If your proficiency rank for a statistic is trained, expert, master, and legendary, your bonus equals your character’s level plus another number based on the rank (2, 4, 6, and 8, respectively). If your character is untrained, your proficiency bonus is +0” (27).
Question: How is it used? (d20 Rolls)
“Proficiency gives you a bonus that’s added when determining the following modifiers and statistics: AC, attack rolls, Perception, saving throws, skills, and the effectiveness of spells” (13).
Perception = Initiative in Most Cases
“Your character’s Perception modifier measures how alert they are. This modifier is equal to their proficiency bonus in Perception plus their Wisdom modifier. For more about Perception, see page 448” (47).
“When choosing what type of roll to use for initiative, lean toward the most obvious choice. The most common roll is Perception…” (498).
“For each kind of saving throw, add your character’s Fortitude, Reflex, or Will proficiency bonus (as appropriate) plus the ability modifier associated with that kind of saving throw” (13).
Melee Strikes and Ranged Strikes (To Hit Only)
“Next to where you’ve written your character’s melee and ranged weapons, calculate the modifier to Strike with each weapon and how much damage that Strike deals. The modifier for a Strike is equal to your character’s proficiency bonus with the weapon plus an ability modifier (usually Strength for melee Strikes and Dexterity for ranged Strikes).
You also add any item bonus from the weapon and any other permanent bonuses or penalties. You also need to calculate how much damage each weapon’s Strike deals. Melee weapons usually add your character’s Strength modifier to damage rolls, while ranged weapons might add some or all of your character’s Strength modifier, depending on the weapon’s traits. See the weapon entries in Chapter 6 for more information” (27).
“For each skill in which your character is trained, add your proficiency bonus for that skill (typically +3 for a 1st-level character) to the indicated ability’s modifier, as well as any other applicable bonuses and penalties, to determine the total modifier for that skill. For skills your character is untrained in, use the same method, but your proficiency bonus is +0” (28).
“A class DC sets the difficulty for certain abilities granted by your character’s class. This DC equals 10 plus their proficiency bonus for their class DC (+3 for most 1st-level characters) plus the modifier for the class’s key ability score” (29).
Armor Class (AC)
“Your character’s Armor Class represents how difficult they are to hit in combat. To calculate your AC, add 10 plus your character’s Dexterity modifier (up to their armor’s Dexterity modifier cap; page 274), plus their proficiency bonus with their armor, plus their armor’s item bonus to AC and any other permanent bonuses and penalties” ( 29).
Increases as you Level = Progression
“…your proficiency bonuses all increase by 1 because you’ve gained a level, so your AC, attack rolls, Perception, saving throws, skill modifiers, spell attack rolls, and class DC all increase by at least 1” (31).
“Increase all of your proficiency bonuses by 1 from your new level, and make other increases to your proficiency bonuses as necessary from skill increases or other class features. Increase any other statistics that changed as a result of ability boosts or other abilities” (31).
Class Centric or Initial Proficiencies
“When you choose your character’s class, they gain a set of initial proficiencies. Proficiencies measure your character’s ability to perform tasks, use abilities, and succeed at checks. Proficiency ranks range from trained to legendary” (68).
“If your character is trained in Perception, a saving throw, or another statistic, they gain a proficiency bonus equal to their level + 2, while if they have expert proficiency, they gain a proficiency bonus equal to their level + 4” (p68)
Examples of Proficiency Bonus Affecting Class-Specific Feats
Barbarian Class Level 12 Feat: Spirit’s Wrath
“The wisp’s attack modifier is equal to your proficiency bonus for martial weapons plus your Strength modifier plus a +2 item bonus, and it applies the same circumstance and status bonuses and penalties that you have” (92).
Rogue Class Level 4 Feat: Sabotage
“Critical Success: You deal damage equal to four times your Thievery proficiency bonus. Success: You deal damage equal to double your Thievery proficiency bonus” (185).
“Your animal companion uses your level to determine its proficiency bonuses” (214).
Skill Checks and Skill DCs
When you’re actively using a skill, often by performing one of its actions, you might attempt a skill check: rolling a d20 and adding your skill modifier. To determine this modifier, add your ability modifier for the skill’s key ability, your proficiency bonus for the skill, and any other bonuses and penalties” (234).
Skill modifier = modifier of the skill’s key ability score + proficiency bonus + other bonuses + penalties
Examples of Proficiency Bonus Affecting Feats
Trick Magic Item (268).
Untrained Improvisation (268).
“Your Armor Class (AC) measures how well you can defend against attacks. When a creature attacks you, your Armor Class is the DC for that attack roll.
Armor Class = 10 + Dexterity modifier (up to your armor’s Dex Cap) + proficiency bonus + armor’s item bonus to AC + other bonuses + penalties
Use your proficiency bonus for the category (light, medium, or heavy) or the specific type of armor you’re wearing. If you’re not wearing armor, use your proficiency in unarmored defense” (268).
“When making an attack roll, determine the result by rolling 1d20 and adding your attack modifier for the weapon or unarmed attack you’re using. Modifiers for melee and ranged attacks are calculated differently” (278).
Melee attack modifier = Strength modifier (or optionally Dexterity for a finesse weapon) + proficiency bonus + other bonuses + penalties
Ranged attack modifier = Dexterity modifier + proficiency bonus + other bonuses + penalties
Spell Attack Roll Spell DC
“If you have the ability to cast spells, you’ll have a proficiency rank for your spell attack rolls, so you’ll always add a proficiency bonus” (447).
Spell attack roll result = d20 roll + ability modifier used for spellcasting + proficiency bonus + other bonuses + penalties
“Many spells allow creatures to defend themselves using either their AC or a saving throw. Two statistics govern how potent your spells are against these defenses: your spell attack roll and your spell DC. When recording these on your character sheet, add together only the numbers that always apply—usually just your ability modifier and proficiency bonus.
Spell attack roll = your spellcasting ability modifier + proficiency bonus + other bonuses + penalties
Spell DC = 10 + your spellcasting ability modifier + proficiency bonus + other bonuses + penalties” (298).
“Some spells, such as dispel magic, can be used to eliminate the effects of other spells. At least one creature, object, or manifestation of the spell you are trying to counteract must be within range of the spell that you are using. You attempt a counteract check (page 458) using your spellcasting ability modifier and your proficiency bonus for spell attack rolls” (305).
“When attempting a check that involves something you have some training in, you will also add your proficiency bonus” (444).
Stacking (Item + Proficiency, but don’t double Item)
There are three other types of bonus that frequently appear: circumstance bonuses, item bonuses, and status bonuses. If you have different types of bonus that would apply to the same roll, you’ll add them all. But if you have multiple bonuses of the same type, you can use only the highest bonus on a given roll—in other words, they don’t “stack.” For instance, if you have both a proficiency bonus and an item bonus, you add both to your d20 result, but if you have two item bonuses that could apply to the same check, you add only the higher of the two” (444).
Playing the Game (repetition)
Pages (446-449) in the Chapter “Playing the Game” repeats most of the previous cited information, such as
· Attack Rolls for Melee and Ranged (446)
· Armor Class (447)
· Spell Attack Rolls (447)
· Perception (448)
· Saving Throws (449) (Fortitude, Reflex, Will)
· Skill Checks (449)
· Counteracting Spells (458-459)
Exploration: Follow the Expert
“Choose an ally attempting a recurring skill check while exploring, such as climbing, or performing a different exploration tactic that requires a skill check (like Avoiding Notice). The ally must be at least an expert in that skill and must be willing to provide assistance. While Following the Expert, you match their tactic or attempt similar skill checks. Thanks to your ally’s assistance, you can add your level as a proficiency bonus to the associated skill check, even if you’re untrained. Additionally, you gain a circumstance bonus to your skill check based on your ally’s proficiency (+2 for expert, +3 for master, and +4 for legendary)” (479).
Skill Increases – Class Chapters
“At 3rd level and every 2 levels thereafter, you gain a skill increase. You can use this increase either to increase your proficiency rank to trained in one skill you’re untrained in, or to increase your proficiency rank in one skill in which you’re already trained to expert. At 7th level, you can use skill increases to increase your proficiency rank to master in a skill in which you’re already an expert, and at 15th level, you can use them to increase your proficiency rank to legendary in a skill in which you’re already a master” (84)
Level and Proficiency Rank are critical for effectiveness in multiple areas.
Ranking up proficiency rank is a decision to consider as you level up. Enhance your focus
Tremendous emphasis on Trained/Expert/Master/Legendary for that +2/+4/+6/+8
Look for creative synergies or areas to hyper focus.
Don’t underestimate “group thinking”
Build your group, Your role.
As you progress so will the enemies. Look at your Bestiary, noting Proficiency Bonuses for
Saves : Fortitude/Reflex/Will