Dwarf

Generally, dwarves are stout, hardy creatures. They stand under 5 feet, but their courage and endurance are matched by their burly build, weighing as much as humans two feet taller than them.

Dwarves live for more than 400 years, so the oldest tend to remember times from a different and bygone era. This tends to make them stubborn in leaving tradition behind, but loyal to those they care for.

Names

A dwarf doesn't own their name. The name is given to them by a clan elder, in accordance to tradition. These names have been passed down for generations, and a dwarf who brings shame to the clan loses it, forbidden to use any dwarven name in its place.

Traits

Ability score increase. Any ability of your choice (generally constitution) of 2.
Age. Dwarves mature at the same rate as humans, but they're considered young until the age of 50. On average, they live about 350 years.
Size. Dwarves are considered medium sized creatures.
Speed. They have a base walking speed of 25 feet.
Darkvision. Accustomed to life underground, dwarves have superior vision in the dark and dim.
Dwarven Resilience. Inheritable Dwarves have advantage on saving throws against poison, and they're resistant to poison damage.
Dwarven Combat Training. They have proficiency with battle-axes, hand-axes, throwing hammers, and war-hammers. Their speed is not reduced by wearing heavy armor.
Tool Proficiency. Choose a proficiency with any artisan tool of your choice.
Stone-cunning. Whenever you make a history check related to the origin of stonework, you are considered proficient in history and add double your proficiency bonus to the check.
Language. You can speak, read, and write Common and Dwarvish.

Subraces

Three main subraces populate the world. These subraces have the main set of dwarf traits along with those listed for each.

Hill Dwarves

Keen senses and deep intuition are the traits of hill dwarves.

Ability score increase. Any other ability of your choice (generally wisdom) of 1.
Dwarven Toughness Your HP increases by an additional point for each level you attain.

Mountain Dwarves

Mountain dwarves are stronger and hardier than normal dwarves. Accustomed to the difficult and rugged terrain of mountains.

Ability score increase. Any other ability of your choice (generally strength) of 2.
Learned Stone's Endurance. You can focus yourself to occasionally shrug off injury. When you take damage, you can use your reaction to roll a d12. Add your Constitution modifier to the number rolled, and reduce the damage by that total. After you use this trait, you can't use it again until you finish a short or long rest.

Duegar: Dwarves of the Underdark

Duegar see themselves as the true manifestation of dwarven ideals.

Ability score increase. Any other ability of your choice (generally strength) of 1.
Tongue of the Underdark. They can speak, read, and write, Undercommon.
Duegar Resilience. Duegar have advantage on saving throws against illusions.
Duegar Magic. At 3rd level, you can cast Enlarge/Reduce on yourself, once per long rest. When you reach 5th level, you can cast Invisibility on yourself, once per long rest. You don't need to meet any of the requirements to cast the spells.