Redstone tick timings, measured
Every delay in Java Edition redstone, in game ticks and seconds, read from the 26.2 game code and confirmed in the simulator against a real server. The game runs 20 game ticks a second; a redstone tick is two game ticks.
| Component | Game ticks | Seconds | Detail |
|---|---|---|---|
| Redstone dust | 0 | 0 | Dust updates in the same game tick as its source. It carries a signal 15 blocks and loses one strength level per block; the 16th block reads 0. |
| Repeater, setting 1 to 4 | 2, 4, 6, 8 | 0.1 to 0.4 | The delay is the setting times two game ticks. A repeater also restores the signal to 15. |
| Comparator | 2 | 0.1 | One redstone tick, in both compare and subtract mode. |
| Redstone torch | 2 | 0.1 | A torch changes two game ticks after the block it stands on changes. More than 8 changes inside 60 game ticks burn it out; it rests for 160 game ticks before it checks again. |
| Redstone lamp turning on | 0 | 0 | A lamp lights in the same tick it is powered. |
| Redstone lamp turning off | 4 | 0.2 | A lamp stays lit four game ticks after its power is gone. This is why a lamp is a poor instrument for a fast clock. |
| Stone button | 20 | 1 | Wooden buttons stay pressed 30 game ticks (1.5 s). |
| Stone or wooden pressure plate release | 20 | 1 | The plate checks again 20 game ticks after you step off. Weighted (gold and iron) plates check after 10. |
| Observer pulse | 2 on, after 2 | 0.1 | An observer notices a change, waits two game ticks, then outputs a two game tick pulse. |
| Hopper transfer | 8 | 0.4 | One item every eight game ticks, so 2.5 items a second. A powered hopper is locked: it neither pushes nor pulls. |
| Tripwire hook | 10 | 0.5 | The hook re-checks its line ten game ticks after it fires. |
| Fresh circuit flash | 2 | 0.1 | A torch change notifies blocks two out before dust settles, so a circuit you just placed can flash once. It is the game, not a bug in the build. |
| Target block | 8 or 20 | 0.4 or 1 | Powered for 8 game ticks when hit by most projectiles, 20 when hit by an arrow. |
Ticks to seconds
Divide game ticks by 20. Multiply redstone ticks by 2 first, then divide by 20. A repeater on setting 4 is 4 redstone ticks, 8 game ticks, 0.4 seconds. A 20 game tick clock period is one second, a 12 game tick torch clock period is 0.6 seconds. The simulator prints game ticks everywhere, so a number on the screen never needs converting.
How delays add up
A signal through a lever, three dust, a repeater on 2 and a lamp: the lever and dust are instant, the repeater adds 4 game ticks, the lamp lights the same tick it is powered, so the lamp lights 4 ticks after the flip. Turn the lever off and the lamp goes dark 4 ticks after the repeater releases, 8 ticks after the flip. Open the repeater circuit and step it to watch exactly that.
Clock periods you get for free
- Repeater clock: 20 game ticks with a setting-4 repeater, 10 high and 10 low.
- Three-torch clock: 12 game ticks, 6 high and 6 low.
- Comparator clock: 8 game ticks, 4 high and 4 low.
- Two-hopper clock with four items: 52 game ticks between empty-hopper markers.
Pulse widths
- Stone button 20, wooden button 30, observer 2, rising-edge detector 4, pulse limiter 8.
- A lamp shows any pulse 4 ticks longer than the wire carries it. Measure on the dust, not the lamp.