About this tool
The D&D 5e Encounter Difficulty Calculator uses the 2014 Dungeon Master's Guide method to tell you whether a fight will be Easy, Medium, Hard or Deadly for your party. Enter your party as a list of character levels and your monsters as a list of Challenge Ratings, and it computes the party's XP thresholds, the monsters' adjusted XP, and the resulting difficulty band. It runs entirely in your browser with the published lookup tables.
Each character has four daily XP thresholds by level (Easy/Medium/Hard/Deadly), and the party threshold is the sum across every member — so a party of four level-5 heroes has thresholds of 1000/2000/3000/4400. Each monster contributes XP by its Challenge Rating (CR 1/4 = 50 XP, CR 1 = 200, CR 5 = 1800, CR 10 = 5900, and so on up to CR 30 = 155000). The raw monster XP is then multiplied by an encounter multiplier that grows with the number of monsters: ×1 for one, ×1.5 for two, ×2 for 3–6, ×2.5 for 7–10, ×3 for 11–14 and ×4 for 15 or more, reflecting how action economy makes swarms deadlier.
The adjusted XP is compared to the four party thresholds to assign a band: at or above Deadly is Deadly, and anything below the Easy threshold is Trivial. Enter party levels separated by commas (for example 5, 5, 4, 4) and monsters as CRs with optional counts using an x (for example 2, 1x2, 1/2 means one CR 2, two CR 1s and one CR 1/2). The tool shows the raw XP, the multiplier, the adjusted XP and all four thresholds so you can tune the fight.