This is How Passive Perception REALLY Works in 5e [With Easy Examples]

“I make a perception roll to see if I can tell that he’s pickpocketing me!” 

Ouch! Has this ever happened to you? You’re a DM trying to set up an exciting encounter when your roll happy players decide when it’s time for them to make a perception check.

Now you have a decision to make.

Do you tell your player no and rob them of the excitement to catch a thief in the act? Or do you let them make a very weird check that takes the rest of the party out of the immersion? Does a natural 20 mean they perceive everything in the room?

There’s a mechanic that solves so many of the problems that perception checks create: Passive Perception

In this article, we’ll be talking about all things passive perception. How it works, when to use it, and how players and DMs can use it to improve the immersion and flow of their games.

What is Passive Perception in 5e?

Passive Perception is a statistic every character in D&D 5e has that determines how aware they are of their surroundings. Instead of rolling dice in certain situations, we have a static number that is equal to 10 plus any modifiers we would normally add to our perception checks.

Note there is a difference between a standard Perception check, and Passive Perception. We’ll get into standard Perception below, but for now let’s focus on Passive Perception!

Passive skill checks in general are special ability checks that, hold onto your seats, don’t require any die rolls. Incredible right? I don’t know about you, but I’ve sat at plenty of roll heavy tables that are just itching to hear the click-clack of those shiny math rocks. 

What this means for perception specifically, is your ability to detect things that you are not actively seeking out. That makes a lot of sense right? The opposite of passive is active, and that’s exactly the situation we’re dealing with here.

Passive Perception Guide - Black Citadel

How Do We Calculate Our Passive Perception?

Calculating Passive Perception

Passive Perception = 10 + any modifiers that apply to your perception check

Any modifier typically just refers to proficiency bonus (if proficient) and your wisdom modifier.

However, if you are under the effects of any abilities that increase your perception in additional ways, those would apply as well.

Example

Your level 3 Fighter has a 12 Wisdom score and is proficient in Perception. Proficient meaning he selected “Perception” as one of his proficiency skills in character creation. Or perhaps you chose the Background Far Traveler, which gives Perception as a skill.

The calculation would be 10 + 2 for proficiency (this number goes up as you level) + 1 from your Wisdom modifier, for a total of 13 Passive Perception.

One of the best examples of passive perception is its use in opposition to the stealth or sleight of hand skills. I’ll give you another example:

Rogal Dorn and his party have entered a ruined castle in search of a mage that is on the run from Waterdeep’s city guard. Unbeknownst to the adventurers, the mage has hired a band of goblins to scare off any intruders while he goes about his work.

When the party enters the castle, each of the six goblins in the entryway will attempt to hide. Check the goblin’s stealth rolls against the passive perceptions of the players’ characters. Any of the goblins that are not spotted will act during a surprise round of combat.”

In this example, goblins roll their stealth checks and we use the passive perceptions of the players to determine which goblins get to attack the players during a surprise round of combat. 

Another common example, sleight of hand, happens when a character tries to pickpocket another character. If a rogue rolls a 14 on their sleight of hand check and the city guard they’re trying to pickpocket has a 17 passive perception, well you’ll probably be calling for an initiative roll at that point. 

While we often use passive perception to notice these sneaky dexterity checks, we can also see it used for simple observations. This is when we as the DMs set the DCs rather than rolling for them.

Footsteps are a great example of this. While just about any character can hear footsteps if they are listening, not everyone can hear them while they’re going about their own business. Even then, very few characters can identify who those footsteps belong to. 

When To Use Passive Perception

Very simply, we use passive perception whenever a character isn’t actively seeking to perceive something. Using our passive score allows us to know what our characters can spot when they aren’t trying.

The concept itself may be simple, but that doesn’t necessarily mean the application is. When it comes to perceiving things I break it down into three broad categories when deciding what sort of check is going to happen.

Active perception, passive perception, and a third category, basic perception are my solution to the problems that plague D&D tables across the world. 

What is Perception in 5e?

Perception is a wisdom-based d20 skill roll that allows you to see, hear, or otherwise detect the presence of something. Examples given in the PHB include listening to a conversation behind closed doors, spotting an obscured object or door, or locating something that’s easy to miss, like an orc obscured by trees.

So you can see the difference here, a Perception check is something you’d let your DM know you’re looking to do. “Can I do a perception check?” You would roll your d20, add modifiers, and let the DM know the results.

It’s actively performed, whereas Passive Perception is always on, it happens regardless of your intent to search for something.

It’s also important to note that perception checks are not some magical spell. The Players Handbook (PHB) mentions an example where a key is hidden beneath clothes in a drawer of a bureau.

A player who asks to walk around the room and make a perception check won’t find that key no matter how high they roll. It’s important to specify what you want to do.

In fact, a player that says they’d like to shuffle through the contents of the bureau might not even need to make a roll, their roleplaying is likely enough to discover what’s hidden.

Basic Perception

While the name of this category exists nowhere in official sourcebooks, this is likely a concept you’re very familiar with. Basic perception refers to any scenario that requires no numbers whatsoever, be them rolls or passive scores. 

This type of perception occurs whenever the DM is describing surroundings. Let’s look at the following DM description of walking into a room. Just to set the scene, you and your party have been searching for the Scroll of Draconic Influence

“You walk into a bright study lined with bookshelves on each wall. There are two leather chairs sitting facing a large ornate fireplace on the northmost wall with a table in between them. On the table you see a pile of documents and an aged scroll that shimmers as if made of a dragon’s scales. This matches the description of the lost scroll you were searching for.”

When we have a description like this, there is no need to perform any sort of perception check to find the scroll, you were told exactly where it is. 

The other situation that can come up is what I mentioned above. If your players are really specific with how they want to search for something you shouldn’t force a number to rule over the outcome.

If a player comes up with an ingenious idea to search for exactly where you’ve hidden something, a 1 on a perception check shouldn’t mean that they can’t see past their nose. 

Active Perception 

This is definitely the most common type of perception, it’s what happens when your players are actively searching things out. Typically, this happens when a player prompts you with “I want to try seeing (something).”

As a DM, it’s up to you to decide if a player needs to roll. Asking to look at a painting shouldn’t take any perception rolls, but asking to spot any hidden messages, discoloration, or similar occurrences on the painting just might need that d20. 

What’s the difference between perception and investigation?

Really, the difference is in the stats these skills fall under. While perception falls under wisdom and is ruled by your ability to intuit and your awareness of the world around you, investigation is an intelligence-based skill that is based on your ability to deduce, and the facts that you can pull out. 

You could find a hidden object with either perception or investigation. Finding an object with perception is being able to simply see where something is out of place, like looking at a Where’s Waldo and finally spotting that turtleneck wearing monster.

Investigation on the other hand is being able to put clues together to decipher the location of that object. If Waldo was always a certain distance from his dog, Woof, and Woof was always near food, you could follow the line of clues back to the red and white menace.

Difficulty Classes (DC)

When we have our players roll any skill checks we’ll want a DC, or difficulty class, in mind. This table should give you a rough idea of how to set the DC for a task.

Task DifficultyDCExample
Very Easy5Smell something burning, determine if food is spoiled.
Easy10Hear footsteps or the details of a conversation in the next room. 
Medium15Find a concealed door; hear whispered conversations; smell the first sign of rain. 
Hard20Find the trigger for a secret door; hear a key being turned in a door.
Very Hard25Notice the tan line of a removed wedding ring.
Nearly Impossible30Successfully follow a street hustler’s three shell game without any guesswork. 

Very easy and nearly impossible skill checks should rarely come up. Very easy essentially means that any character should be able to do it, in which case don’t bother breaking out the dice.

The flip goes for nearly impossible skill checks, which is just a nice DC to throw on a check that your players insist on making even though they shouldn’t be able to.

There are also plenty of things that can change these. Distance and barriers like walls and doors are going to increase the DC accordingly. Typically +1 for every 10 feet and anywhere from +1 to +5 for walls of varying densities is how I judge things.

Difficulty Classes for Passive Perception

  • Setting DCs for passive perception
  • Adjusting DCs based on the environment
  • Focused senses

The rules we use to set the DCs for active perception checks are strikingly similar to those we use for passive perception. The difficulty of a task is still going to determine its DC, but determining what easy, medium, and hard are can be a lot more nuanced.

At the end of the day, it’s up to the DM to decide, but I’ll do my best to give tips and tricks that make it easier.

Easy passive perception checks

This one is a bit of a trap. If you recall from above, the DC for easy tasks is 10. And the way we determine a character’s passive perception score is by adding 10 to any modifiers they would apply to perception. This means most characters will have a passive perception higher than 10, not all though. 

If a character has a negative wisdom modifier they might find themselves below the easy threshold. These characters might not notice something that everyone else would, but that can quickly become overcomplicated.

No one wants to put earplugs in while you explain common features of a room just because wisdom was their dumpstat.

Medium passive perception checks

A DC of 15 is a bit harder to get to, it requires either a high proficiency, a high bonus, or a combination of decent modifiers in both sections. Essentially, wisdom-focused characters will quickly get to this DC while others will be hard-pressed to achieve it. 

An example for this given by XGtE is that characters with a passive score of 15 will be woken up by speech in an otherwise quiet environment. I’m not a heavy sleeper and I can say this only happens to me every so often.

I guess I’ve got like a 14. What this says is character’s that can make these checks have slightly more adept senses than the average D&D character. They might be able to notice things out of the corner of their eye with ease, or pick up on smells without even trying.

Generally a passive perception of 15 in my book means being able to automatically observe a decent amount of things that otherwise rolling a 10 would give you. 

Hard passive perception checks

A character with a passive perception of 20 or greater is easily on par with Sherlock Holmes. That means a maxed out wisdom modifier along with a high level/proficiency bonus, so a lot of experience under their belt.

Another rip from XGtE pg.77 is that whispers within 10 ft. can wake these characters from sleep. That’s pretty impressive, and definitely sets the tone for other things we might allow these players to do.

Saying that they can casually complete medium difficulty perception checks without trying is a bit bland at this point. Characters of this caliber should be able to notice most concealed weapons or a slight favoring of a leg. If perception is being attuned with their surroundings, these characters are finely tuned in.

Focusing your Senses

Skill checks are one of those things in 5e that are left just vague enough for DMs to make spot decisions when necessary. You can’t cover every situation with a list no matter how long the list could be.

Since the closest we get within RAW is a few examples and a rough layout of difficulty, most DMs come up with their own solutions to a lot of the problems that constant rolling can bring up.

An immersion method I use is called Focused Senses, and it reflects how different characters might be more perceptive to different things. My partner, for example, is amazing at spotting deer on the side of the highway.

Her experiences have heightened those senses and I seriously doubt that she could ever be surprised by a deer. If she was a ranger, I’d make sure that her character was always a little better at passively perceiving obscured beasts.

There are two types of focused senses I allow players to engage in, general and specific. 

General is like my partner’s “deer sense” and reflects a character’s upbring, skill set, or experience. When my players build a character I’ll ask them what they’re always on the lookout for, and ask them to base it on their background, race, or class. 

Specific focuses reflect a character’s decision to pay attention to something in the moment. At my tables, a character isn’t constantly paying attention to everything, unless they’re paranoid. When entering a dungeon, or at other times I deem the ‘beginning’ of a situation, I might ask player’s what they’re keeping a lookout for. 

You’ll get responses like traps, secret passageways, footsteps, creatures, etc.  Nothing is too focused, but it can get too broad. Most of the time if a player tries to include too many things I’ll ask them to reign it in a bit, but there is one response I’ll allow; everything.

I’ll ask them if they’re sure they want to be hypervigilant, and if they are, congratulations, they’re paranoid for the duration of the encounter. Or until they get talked down.  

So how does it work?? 

Well, general focuses are pretty simple, I give them an extra proficiency boost to that one instance of passive perception. Since all of these are things we’ve workshopped as a team, they don’t become incredibly unbalanced. In fact, this focused proficiency can make things really exciting.

Specific focuses on the other hand, all depend on the situation. With the focused area the player gives me, I choose a bonus from 1 to the character’s proficiency. I then add the bonus to that category of checks and take it away from the rest of the situations where that character’s passive perception might come into play.

In this way, they’ve focused their passive perception so they don’t need to roll checks as often, but they sacrifice a bit of their perceptive abilities. 

A character’s regular passive perception affects these focuses as well. 

  • 10-14; One general focus, one specific focus.
  • 15-19; One general focus, two specific focuses.
  • 20-24; Two general focuses, two specific focuses.
  • 25+; Two general focuses, two specific focuses. Specific focuses do not result in a deficit to other passive checks.

What if they don’t want a focus? 

Players are at no obligation to take a focus, and can opt out in favor of their normal passive perception score across the board.

What does being paranoid do? 

Players who fall into the trap of being paranoid have a steep consequence for trying to abuse the gift of focused senses. If a character is paranoid they add their proficiency bonus to all passive perception checks.

However, at random intervals I will also inform them that they see, hear, or otherwise perceive danger, and I’ll make it pretty scary. 

“You hear what you instantly recognize as a gelatinous cube behind you,” “You just saw at least two gnolls scurry off into a passageway off to the right.”

Things like this are great to get a party mad at one character who thought they could skirt the rules. It’s also hilarious once they figure out what’s going on and lean into it. 

*If you have players that aren’t good sports you might want to avoid this. I see temper tantrum potential written all over paranoia.

So there you have it, passive perception. I know this is one of a few 5e mechanics that can really derail games into a fit of confusion.Hopefully, you’ve left this article with a much deeper understanding, and the ability to use this set of game rules to make your games so much more immersive and exciting. 

As always, happy adventuring.