Spare the Dying

Necromancy Cantrip (Artificer, Cleric, Druid)

Casting Time: Action
Range: 15 feet
Components: V, S
Duration: Instantaneous

Choose a creature within range that has 0

Hit Points (HP) are a measure of how difficult it is to kill or destroy a creature or an object. Damage reduces Hit Points, and healing restores them. You can't have more Hit Points than your Hit Point maximum, and you can't have less than 0. See also Breaking Objects and Damage and Healing.

and isn't dead. The creature becomes

A creature is Stable if it has 0 Hit Points but isn't required to make Death Saving Throws. See also Damage and Healing.

.

Cantrip Upgrade: The range doubles when you reach levels 5 (30 feet), 11 (60 feet), and 17 (120 feet).

Source: Player's Handbook, p. 318