Knock is a 2nd-level transmutation spell for Bards, Sorcerers, and Wizards. Choose an object you can see within 60 feet, such as a door, chest, padlock or set of manacles. One mundane lock on it unlocks, or a stuck or barred object comes free. An Arcane Lock on it is suppressed for 10 minutes. The spell makes a loud knock that can be heard up to 300 feet away.
Knock is the wizard's lockpick. It needs only a verbal component, works from 60 feet, and doesn't require a roll. A party without a rogue, or with a rogue who just failed, can cast it and move on.
The cost is noise. Every casting produces a loud knock from the target object, audible from 300 feet. In a dungeon, that is a signal to every guard on the floor. Knock also handles only one lock per casting, and it unlocks things without opening them. Someone still has to walk up and pull the door.
Against magic, the spell has one clear job. If the object is held shut by Arcane Lock, Knock suppresses that spell for 10 minutes. It does not end it. When the 10 minutes run out, the lock is back.
| Property | Value |
|---|---|
| Level | 2 |
| School | Transmutation |
| Casting Time | 1 action |
| Range | 60 feet |
| Components | V |
| Material | None |
| Duration | Instantaneous |
| Concentration | No |
| Ritual | No |
| Save/Attack | None |
| Classes | Bard, Sorcerer, Wizard |
| Metric | Assessment |
|---|---|
| Slot Efficiency | Good when the lock is the only thing standing between you and the goal. Poor when a check would do. |
| Action Economy | One action, no roll, from 60 feet. |
| Opportunity Cost | A 2nd-level slot plus a lot of noise. |
When worth the slot: A locked vault, an Arcane Locked door, a prisoner in manacles, or a failed lockpick with the clock running.
When NOT worth the slot: Ordinary locks when your rogue can pick them quietly.
Knock has no higher-level effect. A 3rd-level slot does exactly what a 2nd-level slot does, so always cast it at 2nd.
Why it works: The spell says that if the object has multiple locks, only one of them is unlocked. A vault door with three locks takes three castings, or one casting plus two picks.
This avoids the mistake of: Spending a slot, hearing the knock, and finding the door still shut.
Why it works: Silence says no sound can be created within its 20-foot-radius sphere. Put the sphere on the door, stand outside it, and cast Knock from up to 60 feet away. The knock is created at the target object, inside the sphere. Bards have both spells. Silence needs concentration and Knock doesn't, so one bard can do it over two turns.
This avoids the mistake of: Ringing the dinner bell for the whole dungeon.
Why it works: Manacles are on the spell's list of example targets. You only need to see the manacles and be within 60 feet. In the 2014 rules, escaping manacles without help takes a DC 20 Dexterity check, and breaking them takes a DC 20 Strength check.
This avoids the mistake of: Walking into the guarded cell to pick the lock by hand.
Why it works: While suppressed, the Arcane Locked object can be opened and shut normally. Ten minutes is long enough to search a room and carry the loot out, or to close it again behind you.
This avoids the mistake of: Spending a 3rd-level Dispel Magic on a lock you only need for a few minutes.
Why it's bad: The spell text says a loud knock, audible as far as 300 feet away, comes from the target object. That noise happens every time.
Do this instead: Plan for the noise. Cast it in a Silence sphere, cast it when you are already fighting, or use it as a lure.
Why it's bad: The object becomes unlocked, unstuck or unbarred. The text doesn't say it opens.
Do this instead: Have someone open it, or use Mage Hand, which can open an unlocked door or container from up to 30 feet away.
Why it's bad: Arcane Lock is suppressed for 10 minutes, not ended. After that, the object is magically locked again.
Do this instead: Use Dispel Magic if you need the lock gone for good.
Why it's bad: The spell's target can be an object with a mundane or magical means of preventing access, but the text only describes what happens to mundane locks, stuck or barred objects, and Arcane Lock. What it does to other magical seals is a DM ruling, not rules text. Some items are immune by name: the SRD's Instant Fortress door is immune to Knock.
Do this instead: Ask your DM before you rely on Knock against unusual magic.
These are for DMs and villains protecting something.
The 2024 Player's Handbook keeps Knock as a level 2 transmutation spell for Bards, Sorcerers and Wizards. The text is almost word for word the same. It still targets one object within 60 feet, unlocks one mundane lock, frees stuck or barred objects, suppresses Arcane Lock for 10 minutes, and makes a knock audible up to 300 feet away. The spell itself has no mechanical changes.
Some rules around it changed:
Knock unlocks one mundane lock on an object you can see within 60 feet, or frees an object that is stuck or barred. On an object held by Arcane Lock, it suppresses that spell for 10 minutes. It also makes a loud knock that can be heard up to 300 feet away.
Yes. Every casting creates a loud knock from the target object, audible up to 300 feet away. You can hide it by putting the object inside a Silence sphere and casting Knock from outside.
It suppresses Arcane Lock for 10 minutes. During that time the object opens and shuts normally. After 10 minutes, the Arcane Lock works again.
No. If the object has several locks, one casting unlocks only one of them.
Yes. A set of manacles is one of the example targets in the spell. You need to see them and be within 60 feet.
Bards, Sorcerers and Wizards have it on their spell lists in both the 2014 and 2024 rules. The 2024 Chime of Opening also casts it.
It works on Arcane Lock. For other magical barriers, the spell text says the target can have a magical means of preventing access but doesn't describe what happens, so that is a DM ruling. Some SRD items, like the Instant Fortress, are immune to it by name.
You can cast it with a higher slot, but nothing improves. Knock has no higher-level effect.
Citations: SRD 5.1 (2014 rules), SRD 5.2.1 (2024 rules)
Includes material from the System Reference Document 5.1 and 5.2.1 by Wizards of the Coast LLC, licensed under CC BY 4.0.
This page includes material from the System Reference Document 5.1 and 5.2.1 by Wizards of the Coast LLC, available under the Creative Commons Attribution 4.0 International License. Loreify is not affiliated with Wizards of the Coast.
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