How to calculate passive perception?

Question

For Christmas my kiddo got the D&D Starter Set and we've been going though it and the full rules we downloaded online. I'm having a hard time figuring out how the example listed in the rules gets to a final value of 14.

The example is a level 1 character with wisdom of 15 and a proficiency in perception.

I understand that you start with 10 (base) + 2 (character level) + 2 (wisdom 15) which gets you to 14 but then how does the "proficiency in perception" help or factor in?

What gets more confusing is on one of the pre-generated character sheets has a level 1 character with wisdom of 10 but a passive perception value of 10. If I follow the math from above shouldn't it be 10 (base) + 2 (char lev 1) + 0 (wisdom 10 = 0 bonus) for a final score of 12?

How to calculate passive perception?

Answer 1

The Passive Perception is like normal Perception, but you add 10 instead of rolling the 20-sided die

Passive checks are calculated like so:

10 + all modifiers that normally apply to the check
If the character has advantage on the check, add 5. For disadvantage, subtract 5.

The "all modifiers that normally apply to the check" are the numbers that the player would add to the 20-sided die if they were rolling the ability check instead of using the passive check. These modifiers include:

• the ability score modifier.
• the proficiency bonus, if the character is proficient in the check.
• any miscellaneous bonuses granted by racial traits, class features, feats, spells, etc.

Examples, in increasing complexity

A 1st-level character with Wisdom of 10 and no proficiency in Perception (the pre-generated character example):

• the bonus to Perception is wisdom modifier = 0
• the Passive Perception is 10 + Perception bonus = 10 + 0 = 10.

A 1st-level character with a Wisdom of 15 and proficiency in Perception (the PHB example):

• the bonus to Perception checks is wisdom modifier + proficiency bonus = 2 + 2 = 4
• the Passive Perception is 10 + Perception bonus = 10 + 4 = 14.

A 1st-level character with a Wisdom of 13 and proficiency in Perception who is in surrounded by patchy fog¹:

• the bonus to Perception checks is wisdom modifier + proficiency bonus = 1 + 2 = 3
• the Passive Perception is 10 + Perception bonus - disadvantage = 10 + 3 - 5 = 8.

A 5th-level Bard with a Wisdom of 13, no proficiency in Perception, and the Jack of All Trades² feature:

• the bonus to Perception is wisdom modifier + Jack of All Trades = 1 + 1 = 2
• the Passive Perception is 10 + Perception bonus = 10 + 2 = 12.

A 5th-level character with a Wisdom of 18, proficiency in Perception, and the Observant³ feat:

• the bonus to Perception is wisdom modifier + proficiency bonus = 4 + 3 = 7
• the Passive Perception is 10 + Perception bonus + Observant = 10 + 7 + 5 = 22.

The following are two cropped images of the pre-generated halfling rogue and the pre-generated human fighter respectively, which show similar calculations. Note that the grey dot indicates proficiency.

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1. Vision and Light. In a lightly obscured area, such as dim light, patchy fog, or moderate foliage, creatures have disadvantage on Wisdom (Perception) checks that rely on sight.
2. Jack of All of Trades. Starting at 2nd level, you can add half your proficiency bonus, rounded down, to any ability check you make that doesn’t already include your proficiency bonus.
3. Observant. You have a +5 bonus to your passive Wisdom (Perception) and passive Intelligence (Investigation) scores.

Answer 2

"+ 2 (char level)" is not correct -- not least because you have a level 1 character, not a level 2 character! You are adding +2, but +2 represents the proficiency bonus associated with a character of that level -- and you would not add that number if you were not proficient in Perception.

Here is the section in the rules that outlines how to use a proficiency bonus. In particular, it specifies that the proficiency bonus applies to skills you are proficient in; Perception is a skill that you are proficient in, so you add the proficiency bonus of +2 to Perception checks as well as to your character's Passive Perception score.

Answer 3

Passive perception is 10 + Wisdom + Proficiency bonus (if you have proficiency)

Your original equation including "char level" is incorrect. Check page 61 (the page before your quoted text) under Skills:

In either case, proficiency in a skill means an individual can add his or her proficiency bonus to ability checks that involve that skill. Without proficiency in the skill, the individual makes a normal ability check.

Specifically for passive perception, it would be 10 + your Wisdom bonus, and if you are proficient in perception you could add your proficiency bonus (+2 in this case).