Adventurekeep is described as 'online toolkit for Dungeon Masters to create epic adventures with ease. Adventurekeep provides state-of-the-art tools for building and running 5e adventures'. There are more than 10 alternatives to Adventurekeep, not only websites but also apps for a variety of platforms, including Windows, Mac, Android and iPhone. The best alternative is Roll20, which is free. Other great sites and apps similar to Adventurekeep are D&D Beyond (Freemium), Fantasy Grounds (Paid), Astral Tabletop (Freemium) and Adventurer's Codex (Free, Open Source).
Roll20 is the free, easy way to play tabletop games (such as pen and paper RPGs) online with others. It's completely web-based, so it runs right in your browser. It supports video and voice chat, background music, character sheets, a massive art library, and more!
A fun, easy to use, Open Source tool for tabletop RPG players to manage their characters, campaigns, and parties. The goal is to help you focus more on the game by bringing your paper character sheets into the 21st century.
Standard Action is a tabletop gaming application designed to be simple, but flexible. In game, Standard Action features an interactive game board, live chat, dice rolls, a turn tracker, customizable token stat bars, and much more.
Beyond Tabletop is a set of tools for RPG players with easy-to-use online character sheets and maps. Subscription-free and designed to be used on all devices online. Currently offering a battle map and character sheets for Pathfinder and D&D 5e.
Rolisteam helps you to manage tabletop role playing games with remote friends/players. It provides many features to share maps, pictures and it also includes tool to communicate with your friends/players.
TaleSpire is an online, digital, graphical way of playing classic P&P Role-playing games with your friends. As a DM, build your campaign in-game and invite your players for sessions. To your left you can watch one of our streams to see for yourself.