When you jump, you make either a Long Jump (horizontal) or a High Jump (vertical).
Long Jump. When you make a Long Jump, you leap horizontally a number of feet up to your Strength score if you move at least 10 feet immediately before the jump. When you make a standing Long Jump, you can leap only half that distance. Either way, each foot you jump costs a foot of movement. If you land in Difficult Terrain, you must succeed on a DC 10 Dexterity (Acrobatics) check or have the Prone condition. This Long Jump rule assumes that the height of the jump doesn’t matter, such as a jump across a stream or chasm. At your GM’s option, you must succeed on a DC 10 Strength (Athletics) check to clear a low obstacle (no taller than a quarter of the jump’s distance), such as a hedge or low wall. Otherwise, you hit the obstacle.
High Jump. When you make a High Jump, you leap into the air a number of feet equal to 3 plus your Strength modifier (minimum of 0 feet) if you move at least 10 feet on foot immediately before the jump. When you make a standing High Jump, you can jump only half that distance. Either way, each foot of the jump costs a foot of movement. You can extend your arms half your height above yourself during the jump. Thus, you can reach a distance equal to the height of the jump plus 1½ times your height.
SRD 5.2.1 · CC BY 4.0