Can Monks Use Shields?

Can they? One of my players who love to push the rules, wants to know...

Yes.

The question shouldn't be *can they*. The question should be "what happens when they do?".

well, for one, it wipes out their unarmored AC bonus. Because a Shield is armor. Unless they don't use it, but if they don't use it, then it doesn't give them any benefits.

gets in the way of their attacks, I would think but I haven't looked.

They aren't proficient in shields, which means they suffer a lot of disadvantages (including not getting the +2 to AC, if I remember correctly), and they have a number of features that are disabled by shields. But technically, yes. Not very recommended, though. If they really want to use a shield, Barbarian might be a better fit- their Unarmored Defense can work with shields, whereas Monk's cannot.

Monks can wield a shield without proficiency but will  have disadvantage on any ability check, saving throw, or attack roll that involves Strength or Dexterity, and you can't cast spells

With proficiency they won't have that problem but in both cases it'll also prevent them using many of their abilities:

Unarmored Defence: "while you are wearing no armor and not wielding a shield"
Martial Arts: "You gain the following benefits while you are unarmed or wielding only monk weapons and you aren’t wearing armor or wielding a shield"
Unarmored Movement (2nd, 6th, 10th, 14th and 18th level): "while you are not wearing armor or wielding a shield"

EDIT: It has been noted by some that if you build a strength based monk (rather than dexterity based) and put it in armor, then giving up the features above isn't necessarily a big deal.  In addition NONE of any monk sub-class features are fully negated, but a few do work with unarmed strikes and your unarmed strike might not be used as much if you don't have Martial Arts and some features also focus on Monk weapons which you might be ignoring.  Things get particularly good if you've multi-classed from fighter with Unarmed Fighting for 1d6+Str unarmed attacks and for both the weapon and armor proficiency, then all you miss out on is the Monk capstone of Perfect Self to get Ki Points back when you enter battle with none.  Most of these builds use a two handed weapon rather than one handed weapon and shield though, this way they can still use unarmed strike when you need to and not drop or stow your weapon.

Interestingly I just found out in with my 2024 Druid-Monk Multiclass: DnD Beyond is indeed increasing the AC when I "equip" the shield in this build ... 

Seems that shields do not count as armor for the tool yes

Quote from _FlyingTiger_ >>

Seems that shields do not count as armor for the tool yes

Remember that a shield isn't classified as armor. They are displayed in the same table but they are their own things (SAC for reference).

It was mentioned that this was seen in a Druid/Monk multiclass character.  I suspect that the Unarmored Defense is not actually being used to calculate the Base AC and instead the formula that is typically used for a Druid is being used instead.  Multiclass Druids are proficient in Shields.

Quote from wagnarokkr >>

Quote from Thezzaruz >>

Remember that a shield isn't classified as armor. They are displayed in the same table but they are their own things (SAC for reference).

That's true, but the Monk's Unarmored Defense feature specifically excludes both armor and shields.

Yep, that is also true.

And also the unarmoured defense is indeed checking what loadout is "active" if you equip any body armour with a Monk-(multi)class, the unarmoured defense formula is not applied 

Definitely a bug, can confirm. Equipping a shield while the active AC calculation is Monk's Unarmored Defense is increasing AC by 2 when it shouldn't. (In the case of the character I tested it on, the AC shouldn't change at all, as the Wis mod of +2 should have just canceled out.)

Yeah: Unarmored defense from monk doesn't "turn off" automatically if they equip a shield - Bugs & Support 

Quote from _FlyingTiger_ >>

Interestingly I just found out in with my 2024 Druid-Monk Multiclass: DnD Beyond is indeed increasing the AC when I "equip" the shield in this build ... 

 It doesn't appear that the app was made with the Monk's funky calculations in mind. It's going to add the AC, because that's what it's supposed to do.  

Sorry but I disagree. DnD Beyonce is explicitly promoted as a replacement of paper sheets with the app, the dices and the integration in the own vtt. Also some rules are applied others not.

Edit note: I have to correct myself - I cannot prove with a link where it is "explicitly" promoted as an replacement so I redact this statement.

Besides this, for me it is very "petty" to look for a written statement, while the reality shows a tool which

1) is offering more functionality and comfort than the paper one

2) published, managed and hosted by the IP Owner

3) embedded in a online service which provides you with the rules for sale and use

4) connected with a maps tool which lets you directly role from your digital character sheet.

So for me it is obvious, that WOTC sees the both as valid alternatives. Indeed I did not see sofar a big remark - "please always use the paper version always as the digital one is not working properly"

The character builder is not an ultimate source of truth on math or even rules, unfortunately. There are a lot of features that are not properly implemented on the builder, despite it being pretty much the way that I (and presumably many others) build their characters almost exclusively these days. If a player brought me a paper sheet and said that I was wrong for how I calculated the bonuses their character had because their calculator said they should have X/Y/Z and when I looked at their character I based it on the rules, I would always point to the rules, not the math.

Unfortunately, a lot of people forget to pay attention to the limitations of features like Unarmored Defense, and when the builder doesn't calculate those accurately then people insist that actually the character sheet must be right. I don't think it's malicious 90% of the time, it's just that if the system says it works you assume the system is correct. But any time something more than a little complicated hits D&D Beyond, sometimes just temporarily but sometimes permanently, you tend to see edge case bugs like this one.

I get this of cause, but for me its too simple to say sometimes the tool is working properly and sometimes not. As this is a paid service for the most it should work properly. For me it is even not a "bug" but a source of improper coding.