Concentration in 5e Explained

How does concentration work in 5e?

Some spells say "Concentration" in their duration. These spells last only as long as you keep your focus on them. Concentration has three core rules, and they are the same in the 2014 and 2024 Player's Handbooks:

• One at a time: you can concentrate on only one spell. Casting a second concentration spell ends the first.
• You can drop it: you can end concentration at any time, no action needed.
• Damage tests it: when you take damage, you make a Constitution saving throw to hold on.

Concentration spells include many of the best buffs and control spells in the game, such as bless, haste, hold person and spiritual weapon (2024 version; the 2014 version doesn't need concentration). Losing one at the wrong moment can swing a fight, so the saving throw matters. Roll it on a d20 roller and add your Constitution save bonus in the bonus box.

What is the DC for a concentration check?

The DC equals 10 or half the damage you took (rounded down), whichever is higher. In the 2024 rules the DC can't go above 30.

Most hits deal less than 22 damage, so in practice the DC is usually 10. Each separate source of damage calls for its own save. Three arrows that each hit you mean three saves at DC 10, not one save against the total.

What breaks concentration in 5e?

• Casting another concentration spell: the old spell ends the moment you start the new one.
• Failing a Constitution save after damage: see the DC rules above.
• Becoming incapacitated: this includes being stunned, paralyzed, petrified or knocked unconscious. See conditions in 5e.
• Dying: the spell ends.
• Environment: in the 2014 rules, the DM can call for a DC 10 Constitution save in situations like a wave crashing over you or a ship rolling in a storm.

Casting a spell that does not need concentration does not break it, and neither does attacking, moving or taking other actions.

What are the odds of keeping concentration?

We computed these with a script. Your Constitution save bonus is your Constitution modifier, plus your proficiency bonus if you are proficient in Constitution saves. A natural 1 is not an automatic failure on saving throws in either rule set, so a +9 bonus always beats DC 10.

A typical wizard with Constitution 14 (+2) and no proficiency holds concentration 65% of the time against DC 10. That means a single hit breaks the spell about one time in three. With War Caster the same wizard holds 87.75% of the time.

How does it add up over several hits?

Every hit is a new save, so the risk compounds. At 65% per save, the chance of surviving two hits in a row is about 42.25%, and three hits about 27.46%. At 87.75% (War Caster), it is about 77% for two hits and 67.57% for three.

Should you take War Caster or Resilient (Constitution)?

These are the two feats casters usually pick to protect concentration.

• War Caster: advantage on Constitution saves to keep concentration, plus the ability to cast a spell as an opportunity attack and to perform somatic components with your hands full. The 2024 version also raises Intelligence, Wisdom or Charisma by 1.
• Resilient (Constitution): +1 Constitution and proficiency in Constitution saving throws. The bonus equals your proficiency bonus, so it grows from +2 at level 1 to +6 at level 17.

At low levels, War Caster gives the bigger boost against DC 10. With a +2 bonus, War Caster raises your odds from 65% to 87.75%, while Resilient at level 4 adds your +2 proficiency bonus, plus another +1 if the extra Constitution point raises your modifier, for 75% to 80%. Resilient catches up at higher levels, helps against high DCs, and also protects you from every other Constitution save, like poison and breath effects. If you can, take both: advantage stacked on a big bonus makes losing concentration rare.

Sorcerers, Artificers and Fighter-casters often already have proficiency in Constitution saves from their class, which makes War Caster the better pick for them.

What happens when concentration ends?

The spell ends right away, with no saving throw or delay. Whatever it was doing stops: a held creature can move again, a summoned creature or conjured effect disappears if the spell says so, and a buff like bless stops adding its bonus. A spell that ends early doesn't refund its spell slot.

Concentration also applies to spells you cast from a scroll, a wand or a magic item if the spell itself requires concentration. That spell counts as your one concentration spell, so you can't use an item to run two at once. Plan which spell is worth holding before the fight starts, and pick a non-concentration spell for your next turn when you already have a strong effect up.

How can you protect your concentration?

1. Stay out of melee and use cover; fewer hits mean fewer saves. See cover in 5e.
2. Pick a concentration spell that is worth the risk; don't drop haste to cast a weaker one.
3. Boost your saves. Bless adds 1d4 to saving throws, and a Paladin's aura adds its Charisma modifier.
4. Raise your Constitution score or take War Caster or Resilient.

FAQ

What is the concentration DC in 5e?

The DC is 10 or half the damage you took, whichever is higher. The 2024 rules cap it at 30.

Can you concentrate on two spells at once in 5e?

No. If you start casting a second concentration spell, the first one ends right away.

Does War Caster give advantage on concentration saves?

Yes. In both the 2014 and 2024 rules, War Caster gives advantage on Constitution saves made to keep concentration.

Do you make one concentration save per damage source?

Yes. If you take damage from several sources, such as two attacks, you make a separate save for each one.

Related

• Roll a d20
• Saving Throws in 5e: Full Guide
• Conditions in 5e: Complete List
• Bless 5e