For each tick (1/20 second), a fraction of the block's durability accumulates: tool speed ÷ durability ÷ 30 if the block drops with this tool, or ÷ 100 if it doesn't. When one unit is reached, the block breaks. A fraction equal to or greater than one unit causes the block to break on the first hit.
Speed — 1 with your hand and a foreign tool, and based on material: wooden axe — 2, stone axe — 4, copper axe — 5, iron axe — 6, diamond axe — 8, netherite axe — 9, gold axe — 12. Efficiency adds level² + 1, Speed boosts multiply by 1 + 0,2 × level, underwater speed ×0,2 (with the Diver — no loss), jumping speed ÷5.