Formula Used
Ability modifier = floor((ability score − 10) ÷ 2) Character proficiency bonus = 2 + floor((level − 1) ÷ 4) Saving throw = d20 + ability modifier + proficiency contribution + bonuses − penalties Spell save DC = 8 + proficiency bonus + spellcasting ability modifier + special bonuses Concentration DC = maximum of 10 or half the damage from one source Success probability = favorable exact outcomes ÷ all possible exact outcomes
A saving throw does not normally gain automatic success on a natural 20 or automatic failure on a natural 1. Death saves use their own natural-roll rules.
How to Use This Calculator
- Select the ruleset, class, level, and ability entry method.
- Enter all six ability values and confirm saving throw proficiencies.
- Add permanent, temporary, magical, aura, or custom adjustments.
- Choose a saving throw, DC, roll mode, extra dice, and reroll rules.
- Complete the spell, monster, concentration, or group sections when needed.
- Press Calculate Saving Throws, then copy or export the result.
Example Data
| Example | Inputs | Expected result |
|---|---|---|
| Level 5 fighter Constitution save | CON 16, proficient, PB +3 | +6 before other bonuses |
| Wizard spell save DC | INT 18, level 9 PB +4 | DC 16 |
| Concentration after 30 damage | DC max(10, 15) | DC 15 Constitution save |
| Monster Wisdom save | WIS 14, CR 8, proficient | +5 before custom bonuses |
Understanding 5e Saving Throws
Saving throws test how a creature resists danger, magic, poison, fear, and other harmful effects. Each save uses one of the six abilities and usually targets a stated Difficulty Class. The calculator combines the chosen ability modifier with every valid bonus.
Proficiency comes from a character’s starting class, a monster’s stat block, or another specific feature. Multiclassing does not normally grant the new class’s saving throw proficiencies. Manual controls remain available for unusual builds and homebrew campaigns.
Advantage rolls two d20s and keeps the higher result, while disadvantage keeps the lower result. Added dice can significantly change the success chance near the target number. This page calculates those distributions rather than estimating them.
Spell save DCs use eight, proficiency bonus, and the spellcasting ability modifier. Some magic items or class features can increase that value. The target then rolls the saving throw named by the spell or effect.
Concentration checks are Constitution saving throws triggered by separate damage sources. The usual DC is ten or half the damage, whichever is higher. Several damage instances can therefore require several individual checks.
Death saves work differently from ordinary ability saves. Three successes stabilize a dying character, while three failures cause death. Natural one and natural twenty results also create special outcomes.
Probability results help Dungeon Masters compare encounter pressure and help players understand risky choices. A high modifier can still fail against a difficult DC. Repeated attempts also change the chance of eventual success.
Monster mode estimates saves from ability scores, Challenge Rating proficiency, and selected proficiencies. A published stat block should remain the final authority. Legendary Resistance can turn a failed save into a success when available.
House rules may change minimum rolls, rerolls, automatic outcomes, or bonus stacking. Record those changes in the notes field for clearer exports. Always follow the rules chosen by your table.
Frequently Asked Questions
How is a 5e saving throw modifier calculated?
Add the relevant ability modifier, proficiency when applicable, and all valid bonuses. Subtract any penalties affecting the roll.
Does a natural 20 automatically pass a saving throw?
Ordinary saving throws usually compare the total against the DC. Natural 20 has special meaning for death saves.
Does a natural 1 automatically fail a saving throw?
Not normally for an ordinary saving throw. A natural 1 counts as two failures during a death save.
How does advantage change the probability?
Advantage rolls two d20s and keeps the higher. The exact improvement depends on the required result.
How is a spell save DC calculated?
Use 8 plus proficiency bonus plus the spellcasting ability modifier, then add any specific bonuses.
What is the concentration save DC?
It is usually 10 or half the damage from one source, whichever number is higher.
Do multiclass characters gain more saving throw proficiencies?
They normally keep the saving throw proficiencies granted by their starting class. Other features may add more.
How is monster proficiency determined?
Monster proficiency generally follows Challenge Rating. Published stat blocks may already include final saving throw bonuses.
Can this calculator support homebrew rules?
Yes. Use custom bonuses, penalties, proficiency multipliers, minimum rolls, rerolls, extra dice, and house-rule notes.