Redstone · Timer · Java & Bedrock

How to Make a Hopper Clock

A hopper clock loops a handful of items between two hoppers to make a steady redstone pulse. It is the simplest way to get a slow, reliable tick in a small space.

two hoppers swap the items

a steady on/off tick

Two hoppers feed each other, so the items shuttle back and forth forever. A comparator reads the full one, giving a repeating pulse. More items in the loop = a slower clock.

What you need

Two hoppers (facing each other)

A stack of items to loop

A comparator to read it

Whatever the pulse drives

Items are the timer

Two hoppers pointed into each other never stop trading the same items, so the loop runs forever. A comparator on one hopper reads it as full or empty, and that rise and fall is your clock. The clever part is the item count: more items take longer to drain, so a few extra nuggets turn a fast clock into a slow, multi-second tick, no extra redstone needed.

Quick answers

What is a hopper clock in Minecraft?

It is a redstone timer made from two hoppers that feed each other. The same items shuttle back and forth between them forever, and a comparator reads whichever hopper is full, giving you a steady on/off pulse without any moving redstone.

How do you build a hopper clock?

Point two hoppers into each other so each empties into the next, put a stack of items in one, and place a comparator coming out of one hopper. The items loop, and the comparator output rises and falls on a fixed rhythm you can wire to anything.

How do you change a hopper clock's speed?

The item count sets the period: more items take longer to drain, so the clock ticks slower. Add or remove items to tune it, and use locking with a second comparator or a repeater if you need an exact, even pulse.

What is a hopper clock used for?

Anything that needs a slow, reliable beat: pulsing an auto farm, flashing lamps or beacons, firing a dispenser on a timer, cycling a display, or driving a day-counter. Hopper clocks shine where repeater clocks would be too fast or too long to build.

Hopper clock vs repeater clock, which is better?

Repeater clocks are best for very fast pulses but get huge for long delays. Hopper clocks are compact and great for slow, multi-second timing. Pick the hopper clock whenever you want a long, steady period in a small space.

Do hopper clocks cause lag?

A single hopper clock is cheap because the items stay inside the hoppers rather than lying on the ground. They only add up if you run many at once, so share one clock between contraptions where you can.

Database →

Hoppers & comparators

Look up hoppers, comparators and how items flow between containers.

Guide →

Use a redstone comparator

How the comparator reads the hopper to make the pulse.

The slow clock that never burns out

Items moving between two hoppers set the period

Two hoppers pointed at each other pass a number of items back and forth, and a comparator on each end fires when one runs empty. The period is set by how many items you put in, which makes this the easiest clock in the game to tune to a specific length.

It is built for minutes, not ticks

Each item transfer takes a fixed time, so a hopper clock covers timings a repeater chain cannot reach without dozens of blocks. For anything faster than a second, this is the wrong clock and an observer loop is the right one.

It survives what torch clocks do not

Torch clocks burn out and comparator loops can desync on a chunk reload, while a hopper clock just keeps moving items. That reliability is the reason it shows up in farms that have to run unattended for hours.