Identifying Spells
Use reaction + Arcana check (DC 15 + spell level) to identify a spell being cast. Costs your reaction — can't also counterspell.
Sometimes a character wants to know what spell is being cast or what spell is currently in effect.
Identifying a Spell Being Cast
If a character can see the caster and perceive the casting (visible components, audible words), they can use their reaction to identify the spell. This requires an Intelligence (Arcana) check with a DC equal to 15 + the spell's level.
Trade-off: Using your reaction to identify a spell means you cannot use your reaction for counterspell, shield, or opportunity attacks on that same trigger. You must choose: identify or react.
Identifying a Spell Already in Effect
A character can spend their action to examine a magical effect and determine what spell produced it. This requires an Intelligence (Arcana) check, with the DC determined by the DM (typically 15 + spell level, or a flat DC based on obscurity).
Alternative methods:
- Detect magic reveals the presence and school of magic within 30 feet but does not identify the specific spell.
- Identify reveals all properties of a magic item and spells affecting a creature.
Identifying a Spell on a Magic Item
Some magic items produce spell-like effects. Identify or a short rest focused on the item reveals its properties. Attunement may be required to fully understand the item's capabilities.
Practical Table Use
Many DMs skip the identification check for common spells, especially if the character is a spellcaster who knows the spell. The Arcana check is most meaningful for obscure, rare, or enemy-only spells that the character wouldn't recognize on sight.