# D20 Test *Source: Player's Handbook (2024) p. 364. Available in the Free Rules (2024)* D20 Tests encompass the three main d20 rolls of the game: [ability checks](3-Mechanics/CLI/rules/variant-rules/ability-check-xphb.md), [attack rolls](3-Mechanics/CLI/rules/variant-rules/attack-roll-xphb.md), and [saving throws](3-Mechanics/CLI/rules/variant-rules/saving-throw-xphb.md). If something in the game affects D20 Tests, it affects all three of these rolls. The DM determines whether a D20 Test is warranted in a given circumstance.