Concentration: calculate the damage save and its cap

SRD 5.2.1 · Magic

At the table

  1. After damage, halve the damage taken and round down.
  2. Use the higher of that number and 10, capped at DC 30, for the Constitution save.
  3. Starting another concentration spell, becoming Incapacitated or dying ends concentration without relying on that damage-save calculation.

Example decision

A concentrating caster takes 41 damage from one instance. What Constitution saving throw DC does the glossary give to maintain Concentration?

DC 20.

Half of 41 is 20.5, which rounds down to 20. That is higher than the minimum DC 10 and below the cap of 30. Use damage taken, rather than an earlier damage number before its applicable reductions. If concentration ends through another listed cause, a successful damage save does not undo that cause.

Watch for this mistake

Concentration on the previous effect ends when casting the next concentration spell starts. Do not allow both effects to overlap until the new spell finishes.

Ask the table

What damage was taken, and is there another independent reason concentration already ended?

Source rule

Some spells and other effects require Concentration to remain active, as specified in their descriptions. If the effect’s creator loses Concentration, the effect ends. If the effect has a maximum duration, the effect’s description specifies how long the creator can concentrate on it: up to 1 minute, 1 hour, or some other duration. The creator can end Concentration at any time (no action required). The following factors break Concentration. Another Concentration Effect. You lose Concentration on an effect the moment you start casting a spell that requires Concentration or activate another effect that requires Concentration. Damage. If you take damage, you must succeed on a Constitution saving throw to maintain Concentration. The DC equals 10 or half the damage taken (round down), whichever number is higher, up to a maximum DC of 30. Incapacitated or Dead. Your Concentration ends if you have the Incapacitated condition or you die.

Source: SRD 5.2.1, 179. Online guide.

Source and reuse

This work includes material from the System Reference Document 5.2.1 (“SRD 5.2.1”) by Wizards of the Coast LLC, available at dndbeyond.com/srd. The SRD 5.2.1 is licensed under the Creative Commons Attribution 4.0 International License, available at creativecommons.org/licenses/by/4.0/legalcode.

The explanation, example and table prompt are Table Ready adaptations; source text has been reflowed. This guide and its printable card are available under the same CC BY 4.0 license. Independent reference; no official affiliation. These rules are optional for our system-neutral adventures.