Your Hit Point maximum increases by 1, and it increases by 1 again whenever you gain a level.
Dwarven Toughness
Raw data
{
"srd": false,
"name": "Dwarven Toughness",
"page": 188,
"type": "entries",
"__prop": "raceFeature",
"source": "XPHB",
"entries": [
"Your {@variantrule Hit Points|XPHB|Hit Point} maximum increases by 1, and it increases by 1 again whenever you gain a level."
],
"raceName": "Dwarf",
"basicRules": false,
"raceSource": "XPHB"
}