Anjour's Arsenal is a collection of tools and resources for Dungeons and Dragons 5th Edition and Shadowdark.
This site is pretty new, so there is not a lot of content yet, but you can check out the tools that are currently available below.
D&D Beast Shapes Table
A table of all beasts you can Wild Shape into as a Druid in D&D 5e. Includes filters for level and Challenge Rating.
D&D Encounter Difficulty
A calculator to determine the difficulty of an encounter based on the number of players, enemies and their levels.
Dice Roll Probability Calculator
A calculator to get the probability of a die roll hitting the set Difficulty Class (DC).
Metric System Converter
A converter to convert between the metric system and the imperial system.