Defensive Stats

Defenses in Elden Ring are divided into three main statistics: defense, negation, and resistance. Defense and negation are both used to calculate damage received from an attack, while resistance is used for the buildup of status ailments. While the three are similar and many are granted from the same attributes and items, they each have unique mechanics tied to them.

Defense
Defense (sometimes called "flat defense") is gained from a character's attributes and level :

in the game's data, and diminishing returns are the result of these values being multiplied together.

As an example, let's find the total for the Veteran's Set's physical negation: "6.8% (Helm) / 18.7% (Armor) / 4.7% (Gauntlets) / 10.8% (Greaves)" The real values are equivalent to, etc., which are multiplied together. "0.932 * 0.813 * 0.953 * 0.892 = 0.644116..." To find the value displayed in-game, subtract it from 1 again and convert it to a percentage. The game's UI only displays the last three decimal places, rounding down. "1 - 0.644116... = 0.355884... = 35.588%"

Resistance
Resistance affects the buildup amount required to inflict a status ailment. Different resistances affect different ailments, and are gained by armor and attributes: Immunity for poison and scarlet rot, Robustness for blood loss and frostbite, Focus for sleep and madness, and Vitality for Death Blight.

Resistance is additive and displayed on the stats screen as a number, but represented elsewhere as a bar on the screen. When the bar fills, the ailment is inflicted on the character. For poison, scarlet rot, and frostbite, the bar slowly depletes over the duration of the effect. This duration is dependent on the source of the ailment and not related to the character's resistances. For blood loss, sleep, and madness, the bar depletes instantly once the ailment has been inflicted.

The bar also depletes over time at a set rate depending on the status in question, measured in buildup/sec :