Every skill check and saving throw in D&D 5e is built from three pieces: an ability modifier, your proficiency bonus if you are trained, and expertise if you have it. This calculator assembles the full table for your character so you can fill out a sheet in seconds.
How it works
The three building blocks combine per skill:
ability modifier = floor((score − 10) / 2)
proficiency bonus = 2 + floor((level − 1) / 4)
skill modifier = ability modifier
+ (proficient ? proficiency bonus : 0)
+ (expertise ? proficiency bonus again : 0)
saving throw mod = ability modifier + (proficient ? proficiency bonus : 0)Expertise effectively doubles the proficiency bonus for that one skill. Saving throws use the same ability-plus-proficiency rule but never get expertise.
Example and notes
A level 5 rogue with a Dexterity of 16 has a +3 Dexterity modifier and a +3
proficiency bonus. Proficient in Stealth, the bonus is 3 + 3 = +6. With
expertise in Stealth it becomes 3 + 3 + 3 = +9. Their Acrobatics, if only
proficient, is +6, while an untrained Strength (Athletics) check uses just the
Strength modifier. The tool computes all eighteen skills and six saves at once.
Remember to add anything from feats, magic items, or spells on top of these base
numbers.
Understanding 5e skill checks in depth
Why bounded accuracy matters here
One of 5e’s design goals was bounded accuracy: unlike earlier editions where modifiers could reach +30 or more, 5e caps proficiency bonus at +6 (at level 17–20) and ability modifiers at +5 (score of 20 without magic). This means the gap between a trained character and an untrained one on a given skill never exceeds +6 in proficiency, and often less. A wizard untrained in Athletics still has a reasonable chance of a moderately difficult Athletics check; a barbarian with +6 proficiency in Athletics and a +5 Strength modifier (+11 total) can simply pass most Athletics checks without rolling.
The bounded accuracy design makes this calculator especially useful at character creation — knowing your exact modifiers tells you reliably which checks you will auto-succeed at the typical DC ranges, which you will need to roll for, and which are genuinely difficult.
Which skills get the most use at the table?
Not all eighteen skills are equally common in play. Across a typical campaign:
- Perception (Wisdom) is the most-used skill by far — passive Perception appears constantly as a GM check against hidden threats, secret doors, and ambushes.
- Stealth (Dexterity) and Athletics (Strength) are heavily used in exploration and combat.
- Persuasion, Deception, Insight (Charisma/Wisdom) dominate social encounters.
- Arcana, History, Nature, Religion (Intelligence) come up for knowledge checks, but less frequently unless the campaign has a heavy investigation or lore component.
- Performance (Charisma) is mechanically identical to Persuasion in many edge cases but is used for entertainment, not negotiation.
When choosing skill proficiencies at character creation, weight toward the most commonly contested skills for your playstyle. An Insight proficiency matters enormously in a political intrigue campaign and almost never in a dungeon crawl.
Passive skills — the other use of your bonus
Your passive skill score is 10 plus your skill modifier. It represents what you notice or know without actively trying. The most important passive skills are:
- Passive Perception (10 + Perception modifier): the GM compares enemy Stealth rolls against this. A character with passive Perception 16 will notice most sneaking enemies without ever rolling.
- Passive Investigation (10 + Investigation modifier): some GMs use this to reveal hidden clues automatically.
- Passive Insight (10 + Insight modifier): occasionally used by GMs to check whether a character notices a lie without the player asking to roll.
The tool calculates your full modifier for each skill — add 10 to any of them for your passive value.
Saving throw proficiencies by class
Each class grants proficiency in exactly two saving throws at level 1. The most commonly targeted saves in 5e are Dexterity (many spells and area attacks), Wisdom (domination, fear, hold person), and Constitution (concentration checks, exhaustion). Some classes have lucky saving throw sets: Paladins get Wisdom and Charisma, both high-target saves. Rogues get Dexterity and Intelligence — Dexterity is excellent, Intelligence is rarely targeted. This tool shows your full saving throw table, which also matters for the Help action and the Lucky feat’s applicability.