We've all been in a D&D session where the party has barrelled off the main path and into a cave or mine or crypt, despite the dungeon master's unsubtle hints that they've got absolutely nothing prepared. What's a DM to do? No, not ask Chat GPT - they pull out their favorite random dungeon generator, of course! Dungeon Scrawl, the browser-based dungeon mapping tool owned by Roll20, has just implemented a brand new one, and it's a pleasant reminder of what the world was like before 'generative content' meant 'AI generation'.
Dungeon Scrawl is a very lightweight tool which makes low-fidelity, high-utility, old-school D&D maps. It integrates with Roll20 but you can export the outputs for use in other Virtual Tabletops, and the Dungeon Scrawl web app is free to use. The new random generator tool is a simple starting point, letting you choose some parameters for your dungeon - whether it'll be balanced or forking, how large the rooms will be, their rough shapes - and then it can spit out layouts until you find one you like.
The results are bare-bones, without any dungeon furniture or encounters. It's useful if you just need a dungeon layout you can situate some items and encounters into, but less so if you need a fully good-to-go dungeon. If that's the case, Dungeon Scrawl actually has links to two other random dungeon generators that could help.
First there's the Watabou One Page Dungeon Generator, which spits out a small dungeon map with keyed encounters. It's part of the free Watabou project, which has generators for dungeons, realms, cities, villages, caves or glades, and even buildings. You can actually import the floorplan of the dungeon map into Dungeon Scrawl, but Watabou's own renders look great.
Then there's the 5e Dungeon Generator, one of a frankly absurd 447 random generators hosted on the Donjon site, covering everything from treasure hordes to a campaign frame generator for various different D&D editions. The Donjon generator has less visual flair than Dungeon Scrawl, but it's got far more controllable parameters, and importing the results into Dungeon Scrawl gives you the best of both worlds.
As a DM, I'm a massive fan of tools like this that can assist me when the players need something on the fly. If you want to chat about your favorite DM tools - without any AI generation - come and hang out in the Wargamer Discord community!