FoundryVTT Pathfinder 1 Docs

Formula Data

You can use certain variables and functions in formula data, to automatically calculate certain character attributes.

As a quick reference for most variables, you can also hover over certain parts of your character sheet, or some item sheets.

How to Read

In the following documentation, any time you see something like {str,dex,con}, that means you can substitute any value separated by a comma within the curly braces.

For example, if something says @abilities.{str,dex,con}.mod, that means you can enter one of the following:

General Data

The following variables are always available for formulas, unless specified otherwise.

Variable Description
@details.level.value Total amount of class levels of the character Total Hit Die of the character
@abilities.{str,dex,con,int,wis,cha}.mod Ability modifier
@abilities.{str,dex,con,int,wis,cha}.total Total ability score
@abilities.{str,dex,con,int,wis,cha}.value Base ability score
@attributes.hp.value The current hit points of the character, excluding temporary hit points
@attributes.hp.max The maximum hit points of the character
@attributes.hp.temp The current temporary hit points of the character
@attributes.hp.nonlethal The amount of non-lethal damage on the character Base Attack Bonus Combat Maneuver Bonus Initiative bonus (or penalty) Armor Check Penalty, which is a positive value Armor Class Touch AC Flat-footed AC
@attributes.savingThrows.{fort,ref,will}.total Saving Throw bonus (or penalty) Combat Maneuver Defense
@attributes.cmd.flatFootedTotal Flat-footed CMD Spell Resistance
@size Creature size (as a number between -4 and 4)

There are also some more dynamic variables, such as specific class levels and skills bonuses.
To see what you need to enter for those kinds of values, open a class
and hover over the level, or hover over a skill.

Damage Formulas

Some items (such as weapons, feats and spells) can have Damage Formulas and Effect Notes.
The following variables are available for these formulas:

Variable Description
@critMult The critical hit multiplier, which is always 1 on a normal hit, and whatever is set as the item’s critical multiplier on a critical hit
@ablMult The bonus ability multiplier, which is usually 1, but can also be 0.5, 1.5, or 2 (and maybe other values in the future), depending on what’s set up
@critCount What critical damage iteration we’re currently at. For normal damage, this equals 0. For the first critical damage iteration, this equals 1, the second 2 and so on.

Spell Formulas

Spells have the following variables added to what’s useable in their formulas:

Variable Description
@cl Caster Level of the spellbook (also available for the Concentration formula)
@sl Spell Level of the spell

Buff Formula

Buffs have the following variables added to what’s useable in their formulas:

Variable Description
@item.level The buff’s level


You can also apply some math functions to formulas.
Together with nested die (which can be obtained from the Roll Extended module (see Home)), this can create some useful functionality.

Every function of the JavaScript Math object is available, save for the random function. You shouldn’t put Math. in front of the function name.

Some examples:

Expected Location Formula Effect
Any max(3, Returns the total number of hit die, but always at least 3
Spell (max(1, floor(@cl / 2)))d6 Rolls a number of d6 equal to half your Caster Level, but roll at least 1 dice


There is another function for use in formulas besides those from the JavaScript Math object.

sizeRoll(c, s[, size[, crit]]) Available Since: 0.43

This function will take 2 to 4 parameters.
The first parameter (c), is the amount of die you are going to throw.
The second parameter (s), is the sides per die you are going to throw.
The third parameter (size), is the target size, which defaults to 0 (Medium).
The fourth parameter (crit), is the critical multiplier, which defaults to 1.

The way this function works is it takes the first two parameters (c and s), which should represent the die as if a Medium creature would roll them, then takes the third parameter (if given) to changes the original die to account for the size changes (see

For example, if you have a Longsword (a 1d8 damage weapon for Medium creatures), but you want to roll the damage as if you were Huge (2 size categories higher than Medium), you would insert sizeRoll(1, 8, 2). It then outputs a number as if you rolled 3d6, effectively (since 1d8 becomes 3d6 for Huge creatures).

You can also combine this with the @size variable to automatically change the die based on the actor’s size. An example: sizeRoll(1, 6, @size-1), to roll the die as if you were a creature of 1 size smaller than you actually are.

Note that this function will not be multiplied on critical hits automatically. If that is desired, you will need to enter that in the fourth parameter, like sizeRoll(1, 8, 0, @critMult).


Certain fields allow you to put in notes, which will be shown on roll messages.

These include the CMB notes on the Attributes tab of your character sheet, the Concentration and Caster Level notes in your character’s spellbooks, the Notes sections of skills, the Save notes in the Defense tab, the Attack and Effect notes on certain items (like weapons, feats and spells), and Context notes on the Changes tab on certain items (like buffs).

These notes can have inline rolls included, which will be rolled at the appropriate time.

To create an inline roll in these fields, put the formula between double square brackets. Here’s some examples:

Note Example Output
[[1d6]] Strength penalty for [[1d4]] rounds 5 Strength penalty for 2 rounds
DC [[10 + floor(@classes.fighter.level / 2) + @abilities.wis.mod]] DC 14
Last updated on 6 May 2020
Published on 6 May 2020