How Divine Smite Works in 5e

Divine Smite is a level 1 Paladin spell you cast as a Bonus Action right after you hit with a melee weapon or an Unarmed Strike. The target takes an extra 2d8 Radiant damage (9 on average), plus 1d8 if it is a Fiend or an Undead, plus 1d8 for each slot level above 1. You decide after you see the hit, so a smite is never wasted on a miss. Because it takes your Bonus Action, you smite at most once a turn. From level 2, Paladin's Smite lets you cast it once per Long Rest without a slot. Below: the rules quoted, what each slot buys, and why you should smite your first hits rather than wait for a crit.

The rule

Casting Time: Bonus Action, which you take immediately after hitting a target with a Melee weapon or an Unarmed Strike

Range: Self. Component: V. Duration: Instantaneous.

The target takes an extra 2d8 Radiant damage from the attack. The damage increases by 1d8 if the target is a Fiend or an Undead.

Using a Higher-Level Spell Slot. The damage increases by 1d8 for each spell slot level above 1.

The Paladin feature at level 2:

Paladin's Smite. You always have the Divine Smite spell prepared. In addition, you can cast it without expending a spell slot, but you must finish a Long Rest before you can cast it in this way again.

Four things follow from those lines:

• Melee only. A bow or a crossbow cannot smite; a sword, a mace or your fist can.
• One smite a turn. It costs your Bonus Action, and you have one. With Extra Attack you hit twice but still smite once.
• It is a spell. It needs a verbal component, so you cannot smite while you cannot speak.
• One slot per turn. "On a turn, you can expend only one spell slot to cast a spell." Cast Bless with a slot on your turn and you cannot also smite with a slot. The free Paladin's Smite spends no slot, so it still works.

What each slot buys

There is no cap: a level 5 slot gives 6d8, and 7d8 against an Undead. But per slot level, the level 1 slot is the best deal: 9 damage per level, against 6.75 for a level 2 slot and 5.4 for a level 5. Spend low slots on smites, and save the high ones for spells only a high slot can do, unless you need one creature down right now.

Crits double the smite

When you score a Critical Hit, … roll the attack's damage dice twice … If the attack involves other damage dice, such as from the Rogue's Sneak Attack feature, you also roll those dice twice.

Smite dice are damage dice of that attack, so they double too. A level 1 smite on a crit is 4d8 (18), 6d8 (27) against an Undead.

What it does at level 2

A level 2 Paladin with Strength 16 hits at +5 with a Longsword (1d8 + 3). Chance to drop a Ghoul with a single swing:

The Paladin hits 70% of the time. A Ghoul is Undead, so the slot 1 smite is 3d8. Average damage of a hit on the Ghoul: 7.5 with no smite, 21 with a slot 1 smite, 39 on a crit.

Smite now or wait for a crit?

Waiting for a crit sounds clever: the smite dice double. It is not. Take the same Paladin with two level 1 slots, six swings at an AC 14 Undead (a Wight's AC), and three plans:

A crit is 1 roll in 20; a hit is 12 in 20. Over six swings you most likely never crit, so slots held back for crits mostly go unspent. Smite the first hits. If you crit with a slot still in hand, that is the time to spend your highest one.

Later levels

• Level 5: Extra Attack (two swings, still one smite a turn) and four level 1 plus two level 2 slots.
• Level 11, Radiant Strikes: every melee hit deals an extra 1d8 Radiant, with no slot and no Bonus Action. With Strength 20 and +9 to hit against AC 15, a Longsword swing averages 10.95 damage before any smite.
• Oath of Devotion, level 15, Smite of Protection: "Whenever you cast Divine Smite, you and your allies have Half Cover while in your Aura of Protection."

The Paladin's full slot table is in How Spell Slots Work; the crit rule in Damage and Critical Hits.

• Casting time: Bonus Action after a melee hit.
• Damage: 2d8 Radiant, +1d8 per slot level above 1, +1d8 against Fiends and Undead.
• Free cast: once per Long Rest, from Paladin level 2.
• Best slot: level 1, on your first hit.

Every number here comes from the d20 and the damage dice. The Book of Dice covers both in Part I, The Object. The odds here are computed exactly from the dice above; the six-swing plans are exact expected values.

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.