Dungeons & Dragons dice roller with advantage/disadvantage, attack vs AC, damage combos, critical hit detection, and full D&D DC/dice reference tables.
Built for Dungeons & Dragons, this roller handles the common 5e dice patterns in one place. You can roll attacks with advantage or disadvantage, combine weapon dice with bonus damage dice, compare the result against AC or DC, and detect natural 20s and natural 1s automatically.
Presets cover the usual D&D cases such as attack rolls, ability score generation, weapon damage, Fireball, Sneak Attack, and Eldritch Blast. You can also build a custom dice expression when the spell or feature does not fit a preset.
That makes it a quick replacement for table dice when you want the math done immediately and the result still readable in D&D terms.
D&D turns a lot of small dice rules into one combat turn: attack roll, crit logic, damage dice, and situational modifiers. Keeping those pieces together in one roller saves time and reduces misreads when the table is moving quickly.
The reference tables also make it easier to compare common DCs, attack thresholds, and standard damage expressions without opening another tab or flipping through notes.
Attack: d20 + ability mod + proficiency ≥ AC. Damage: weapon die + ability mod. With advantage: roll 2d20, take higher. Critical hit: double all damage dice (not modifier). P(nat 20) = 5%.
Result: 1d20+7 with advantage → rolled 14, 19 → kept 19 + 7 = 26 ≥ AC 18 → Hit!
With advantage, two d20s were rolled: 14 and 19. Keeping the higher (19) and adding +7 gives 26, which beats AC 18.
Every attack in D&D 5e follows the same core mechanic: roll d20 + attack modifier, compare to target's AC. If you meet or exceed the AC, you hit. Then roll damage dice + ability modifier. Critical hits (natural 20) double all damage dice but not modifiers.
The beauty of bounded accuracy means that a +1 bonus is always meaningful — it converts exactly 5% of misses into hits. This is why magical weapons with even a +1 bonus are prized treasures in the 5e economy.
Several D&D features modify dice beyond simple addition. Bardic Inspiration adds a die (d6 to d12) to a roll after seeing the result. Portent (Divination Wizard) replaces a d20 roll entirely. Savage Attacker lets you reroll weapon damage and take either result. Understanding these stacking interactions is key to optimization.
The Lucky feat stands out: three times per day, you can roll an extra d20 on any attack, check, or save. With advantage, this effectively gives you "super advantage" (best of three).
Against AC 15 with +7 to hit: base 65% hit rate, 5% crit. With advantage: ~88% hit, 9.75% crit. Against AC 20 with +7: base 40%, with advantage ~64%. These numbers drive tactical decisions — knowing your exact hit rate helps determine whether Power Attack, Sharpshooter, or Great Weapon Master is worth the -5 penalty in any given situation.
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Roll two d20s and take the higher result. Multiple sources of advantage don't stack — you only ever roll two dice. Advantage and disadvantage cancel each other out.
It's an automatic hit regardless of AC, and it's a critical hit. You roll all damage dice twice (but add the modifier only once). Some features like Brutal Critical add extra dice on crits.
Attack mod = ability modifier (STR for melee, DEX for ranged/finesse) + proficiency bonus (starts at +2, maxes at +6). Magic weapons add their bonus too.
Your proficiency bonus is level-based: +2 at levels 1-4, +3 at 5-8, +4 at 9-12, +5 at 13-16, +6 at 17-20. It applies to attack rolls, saving throws, and skill checks you're proficient in.
Yes. Use the 4d6 drop-lowest preset and roll six times to generate a standard ability score array.
For crits, double your dice count (e.g., 2d8 instead of 1d8 for longsword) and add the modifier once. Use the multi-group dice system to add all dice together.