Tabletop RPG Map editor 2 - RPG Map II is a “tabletop RPG” oriented map maker, created with the “keep it clean & simple” philosophy in mind.
donjon.bin.sh - Freely accessible online collection of random generators for tabletop games.
Mipui - An online grid-based map editor for games, with real-time collaboration.
DUNGEONFOG - Online authoring tool to draw rpg maps & dungeons, create dynamic notes and share your maps online. Create dungeons, world maps and more with the easy to use map editor and create your game master notes dynamically.
RPG map editor - Simple online map editor.
Inkarnate - A free-form map editor for role-playing games, focusing on overland and continental maps.