D&D DC Reference & Calculator
Pick an activity, choose terrain or creature CR, toggle conditions, and see the final DC and exact success probability in real time.
Interactive Tool
DC Calculator
Select a category and activity. Adjust terrain, conditions, and your bonus to see the live result.
Quick Reference
Standard DC Scale
FAQ
Difficulty Classes: Q&A
What is a DC in D&D?
A Difficulty Class (DC) is the number a player must meet or beat on a d20 roll plus their modifier. DC 10 is easy, DC 15 medium, DC 20 hard, DC 25 very hard.
How is success probability calculated?
P = (21 + bonus − DC) ÷ 20 × 100%, clamped to 0–100%. Example: +5 vs DC 15 = 55% success.
How do terrain and conditions affect DC?
Terrain sets the base DC (forest DC 10, jungle DC 15, desert DC 17). Conditions like darkness (+5), heavy rain (+2), or time pressure (+3) stack on top. A good map (−2) or local guide (−5) can offset them.
How does Crafting DC scale with rarity?
Common crafting tasks (DC 10–12) are achievable by any trained alchemist. Rare compounds and exceptional brews push to DC 15–17. Legendary recipes can reach DC 20+.