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The Best Way To Determine Spell Save DC – Defense Against The Arcane Arts

How anticlimactic would it be to fling your final spell towards an abyssal demon, only for it to fizzle out? If you want your spells to stick more frequently, you’ll want to keep your spell save high.

But, what is a spell save and how do you boost it up?

Answering that question is one of the first steps you can take towards spellcasting mastery in D&D 5e. 

What is a Spell Save DC?

A spell save DC is the target number that a creature has to hit with their saving throw to succeed on the throw. This DC is calculated according to your class’s Spellcasting feature, meaning that the spell save DC is different depending on your character’s class and ability scores. 

When a spell with a saving throw requirement is cast, each target of the spell has to make the listed saving throw against the spell save DC.

For example, if a wizard casts a fireball into a group of bandits, each bandit in the radius has to make a Dexterity saving throw against the wizard’s spell save DC.

A spell save DC is the DC you’ll use for every spell that class or creature casts. There aren’t any separate calculations across different schools of magic or between spells that call for different saving throws.

While this may have been the case in the older editions, D&D 5e streamlined the calculation so players don’t lose track of what their spells can do!

How Do We Calculate Spell Save DC?

To figure out what your spell save DC is, you’ll need to look at the Spellcasting feature for your class.

Along with rules about your spells known/prepared and spell slots per day, there should be some text about how to calculate your spell save DC. Following that calculation will give you your spell save DC.

Here is the generalized way that spell save DCs are calculated: 

Spell Save DC and Spell Attack Modifier Calculation

Spell save DC = 8 + your proficiency bonus + your spellcasting modifier

Spell attack modifier = your proficiency bonus + your spellcasting modifier

In other words, once you calculate your spell save DC at level one, you won’t have to do it again until your spellcasting modifier or proficiency bonus goes up.

For most cases, you’ll see your spell save increase steadily over time, usually by one.

Spell Save DCs for Multiclassing

For multi-classed characters that have different spellcasting features, things are a little harder. While your spell slots will increase based on the Multiclass Spellcaster table on page 165 of the Player’s Handbook, your spell save DC isn’t the same across classes. 

Different classes have different calculations for their spell save DC thanks to sometimes requiring different ability scores from one another.

For example, a wizard uses Intelligence for their spellcasting, while a cleric uses Wisdom.

In this case, you’ll need to calculate your spell save DC for each class and keep them separate. Both values will increase with your proficiency bonus, but only the spell saves related to your boost ability score will be affected when your ability scores go up.

Intelligence boosts are great for wizard spells but don’t matter for cleric spells. 

When Do We Use a Spell Save DC?

Spell saves come up when you cast or are the target of a spell that calls for a saving throw. In both cases, you’ll refer to the spell’s description to find out what saving throw is being called for.

A spell can call for any of the saving throws, including some rare ones like Strength or Charisma.  

The target rolls a d20 and adds their saving throw bonus to the result and compares it to the spell save DC. If the target meets or exceeds the listed DC, they succeed.

If it’s below the spell save, they fail. A spell description provides what happens on a success or failure, so read the spell all the way through to find out what happens to your targets in either case. 

How to Improve Your Spell Save DC?

With everything laid out about what spell save DCs are and when to use them, it’s time to ask: how do you make the most out of your spell saves? How can we get our spells as powerful as they can be?

There are two main ways that you can improve your spell save DC: increase your proficiency bonus or increase your spellcasting ability score. Both of these values factor into your spell save DC no matter which class you play as.

As long as your character levels up and boosts the ability score related to their spellcasting, you’ll see your character’s spell save DC increase over time. 

Magic items also boost your spell save DC. While magic items are considered an optional rule for D&D 5e, most tables use them. As a spellcaster, you’ll want to look out for items that provide a static boost to your ability scores, proficiency bonus, or spell saves themselves.

Items like the tome of clear thought, the Ioun stone of mastery, or the arcane grimoire can all boost your spell save DC. 

Frequently Asked Questions

Here are some of the questions that tend to come up when talking about spell save DCs:

How Do Spell Saves Work?

Spell saves are calculated by adding your proficiency bonus and your spellcasting modifier for your class to eight. That total is the spell save DC targets of your spells have to meet or exceed to succeed on the saving throw.

Targets of the spell will roll a d20 and add their saving throw bonus for the save the spell calls for. 

What Gives Disadvantage on Saving Throws?

Certain status conditions, such as restrained or the third level of exhausting, give disadvantage on some or all spell saving throws. There are class features that can force monsters to roll with disadvantage as well, such as the Eldritch Knight’s Eldritch Strike or the Arcane Trickster’s Magical Ambush. 

What is the Highest Spell Save a Character Can Reach?

Your proficiency bonus caps at +6 at level 17 and your ability scores can’t go about 20, which is a +5 modifier. This means that, without access to any magic items, the highest a player character spell save DC can reach is 19.

Magic items exist that increase your ability scores above 20, boost your proficiency bonus, and otherwise give a boost to your spell save DCs, though.