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DJ metronome.
A metronome that counts bars and phrases rather than beats, because that is the count a mix is planned on. Pitch fader instead of a number box, a nudge that behaves like a platter, and two trainers that make counting harder on purpose.
Tempo
Pitch fader
+0.00% · from 128.00
One millimetre of a 100 mm fader at ±8% is 0.205 BPM here — which is why a matched pair still drifts.
Bar of 8
1
Phrase
1
Beat
Phrase
Space to start · arrows to nudge · T to tap
Sound
Subdivision
Beats in a bar
Bars in a phrase
Accents
Click a beat to cycle it: accent, normal, silent.
Reset
The click goes away for a few bars and comes back on the one. If you were counting you are still with it; if you were following, you are not. It is the same thing a breakdown does to you, and it is the only way to find out which of the two you have been doing.
A second click, a fraction of a BPM away from the first. They start as one sound and come apart from there — which is what two decks do when the pitch is nearly right, and why “nearly” does not survive a phrase.
Nothing here is recorded, uploaded or sent anywhere — the click is generated in this tab, so the page works with the network off once it has loaded.
The difference
A DJ metronome is a different instrument.
Ask a musician what a metronome is for and they will say keeping time. Ask a DJ and you get a different answer, because keeping time is what the record already does. What a DJ loses is not the beat — it is the bar. Which of the eight are we on. Is the next drop four bars away or twelve. That is the count a mix is planned on, and it is the one every metronome ever made throws away by resetting at four.
So this one counts to eight, and shows the phrase filling up as it goes. The four dots are still there because the beat is where your foot goes, but the number the size of a clock face is the bar, and it is the number you should be reading.
The tempo control is a pitch fader for the same reason. Nobody in a booth thinks four BPM faster; they think three percent up, on a fader with a range printed beside it. Both numbers are on screen because both are used — and the line under the fader is the uncomfortable one: at ±8% over 128 BPM, one millimetre of a 100 mm throw is 0.205 BPM, which is more than enough to lose a mix inside a phrase.
And the nudge is held rather than tapped. Holding it runs the click a few percent fast or slow for as long as you hold it, and letting go leaves the beat where you pushed it to. That is a platter. A button that jumps the beat by a fixed amount is a different gesture, and it teaches a reflex you cannot use on anything.
Evidence
How accurate it is, and how we know
Measured 2026-08-12 by rendering an hour of clicks and reading the position of every one of them out of the audio.
Every metronome says it is accurate. Here is the number and the method, so you can decide whether it means anything.
An hour of clicks at 128 BPM was generated and the exact position of every one of the 7,681 of them was read back out of the audio itself — not out of what the metronome believed it had done, which is a check that always passes. The worst was 0.5 of a sample from where the tempo puts it, or 0.011 ms. The last one was exactly where it should be.
The last one is the number that matters. Anything that adds up its own beat lengths gets worse the longer it runs; this works out each beat from its position in the count, so an hour in is no different from four bars in. It also cannot be pushed off by anything happening on screen — the count lives with the sound rather than with the page.
To be exact about that zero, because it is the sort of number that deserves it: the only error left is that a beat almost never falls precisely on a sample, so it goes to the nearest one — never more than half a sample, whatever the tempo. It happens to come out at zero here because an hour of 128 BPM at this rate lands on a whole sample exactly. What is true at every tempo is the half-sample bound, and that it is the same at the end as at the start.
A timer can only be given a whole number of milliseconds. Almost no tempo is a whole number of milliseconds, so a metronome built on one runs at the nearest it can get and loses the remainder on every beat, for as long as you leave it on. This is arithmetic rather than a test of anybody’s product — but it is why the demo on most metronome pages is at 120.
120 BPM is the exception, and it is the reason it is everywhere: a beat at 120 is exactly 500 ms, so it is the one tempo where the cheap way is also the right way. At 128 the same metronome is 5.76 seconds out by the end of an hour.
| Tempo | A beat is | Timer gives | Slips | Audible by | After an hour |
|---|---|---|---|---|---|
| 120 BPM | 500 ms | 500 ms | — | never | — |
| 124 BPM | 483.871 ms | 483 ms | 0.871 ms/beat | beat 23 | 6.48 s |
| 126 BPM | 476.19 ms | 476 ms | 0.19 ms/beat | beat 105 | 1.44 s |
| 128 BPM | 468.75 ms | 468 ms | 0.75 ms/beat | beat 27 | 5.76 s |
| 174 BPM | 344.828 ms | 344 ms | 0.828 ms/beat | beat 24 | 8.64 s |
Practice
The two things worth practising.
Almost everybody who thinks they are counting bars is following the sound. It is a good enough substitute for months, and then a breakdown arrives, the drums stop, and there is nothing left to follow. The people who come out of it on the one are counting; the people who do not are guessing.
The gap trainer is the only honest test of which you are. Set it to eight on, eight off. The click and the bar counter both disappear — deliberately, because a counter you can watch is a thing to follow — and come back on the top of a phrase. Either you are with it or you are not, and there is no partial credit.
Turn on the second click and set it a tenth of a BPM away — which is finer than you can set a pitch fader by hand. It starts as one sound. Count along, and somewhere around bar 14 it stops being one sound, and by bar 41 you would be reaching for the platter.
That is not a defect in the tool, and it is not a defect in your ears. Two constant tempos separate at 1.46 ms a bar at that setting and there is nothing either of them can do about it. Push it to half a BPM and you get 7.3 ms a bar, which is a flam inside 3 bars. The transition timer works the same arithmetic out for two actual records; this is where you get to hear it.
Next
Where to take the count
A metronome is a constant and a record is not, which is the one thing it cannot teach you. When the count is solid here, take it to a real track: the phrase counter reads the tempo and the first downbeat off a file you drop on it and counts the bars of that record while it plays, so you can check your count against the arrangement rather than against a click. The cue point calculator then puts the answer somewhere useful — where the cue has to go for the drop to land 32 bars after you press play.
And when the counting is not the problem any more, the problem is which record to count into. That is the rest of this site.
Frequently asked
Common questions
What is a DJ metronome and how is it different from a normal one?+
A normal metronome counts to four and starts again, because that is all a musician reading a bar needs. A DJ needs the bar number — whether this is the third of eight or the seventh — because that is what decides when the next record comes in, and losing it is what makes a mix land in the wrong place. This one counts bars and phrases on screen while it clicks, has a pitch fader with the ranges printed on a player rather than a box you type a number into, and lets you nudge the beat forward and back the way you would push a platter.
How do I practise beatmatching with a metronome?+
Set it to the tempo you play at, put one headphone on it, and play a record against it on a deck with sync off. Your job is to keep the record on top of the click, using the fader for tempo and the platter for position, and the metronome is the honest partner because it will never drift towards you. Start with the kick voice rather than the click — matching a kick to a kick is the thing you will actually be doing. When that is easy, turn on the second click a tenth of a BPM away and listen to how long it takes to come apart.
How accurate is this metronome?+
Measured rather than claimed. Rendered for an hour at 128 BPM, the 7,681 clicks in it land within 0.5 of a sample of where the tempo puts them — 0.011 ms at the worst — and the last click is no further out than the first, because each one is worked out from its own position in the count rather than added to the one before it. For comparison, a metronome driven by an ordinary timer can only be given a whole number of milliseconds, and a beat at 128 BPM is 468.75 of them, so it runs 0.75 ms fast every beat: audibly wrong inside 27 beats and 5.76 seconds out after an hour.
Why does the flashing light look slightly behind on some devices?+
It is not behind — it is on time, and the sound is late. Every playback path adds a delay between the moment a sound is made and the moment it leaves a speaker: a few milliseconds through a laptop, tens of milliseconds through an interface, and up to a fifth of a second over Bluetooth. Most metronomes flash when they make the sound, which means the light is early by exactly that much. This one asks the machine what is being heard right now and holds the light back to match, so what you see is what you hear. The number it measured on your device is printed under the transport.
What are the 8, 16 and 32-bar settings for?+
They set what the bar counter counts up to. Dance music is written in eights, so eight is the default and the one to leave it on: across 555 records this site has measured, 60.9% of the sections in them are within a bar of a whole number of 8-bar phrases, against 39.5% for boundaries scattered at random over the same records. Sixteen and thirty-two are the same count read at the resolution a long intro or a full breakdown is written in.
What does the "hold the count" trainer do?+
It plays for a number of bars, goes completely silent for a number of bars, and comes back on the one. While it is silent the bar counter stops too, so there is nothing to follow and nothing to check against until the click returns. If you are still with it when it does, you were counting. If you are not, you were following the sound — which works perfectly right up until the breakdown, where there is nothing to follow and the count is all you have.
Why does the second click drift away from the first?+
Because it is set to a different tempo, and two tempos separate at a fixed rate. Half a BPM out at 128 slips 7.3 ms every bar, so the two are audibly flamming inside 3 bars and a mess by bar 8. A tenth of a BPM — finer than a pitch fader can be set by hand — buys 14 bars. That is the whole argument for beat grids, and the point of putting it here is that reading it is not the same as hearing it happen.
Does it keep my settings?+
Yes. Tempo, sound, fader range, meter, phrase length and the accent pattern are all remembered in this browser, so the tempo you play at is the tempo it opens on. Nothing is sent anywhere — it is stored on your own machine and clearing your browser data clears it.
Can I use it while the tab is in the background?+
Yes. The click keeps perfect time whether or not the tab is on screen, because the count runs on the audio side rather than on the part of the browser that gets paused when you look at something else. The lights stop moving in a hidden tab — that is the browser, not the metronome — and pick up in the right place when you come back.
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Beatmatch trainer · DJ ear training · Phrase counter · Transition timer · BPM tapper · Beats to time · Cue point calculator · Pitch and tempo · Key & BPM finder · Beatmatching · Phrase · All tools
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DJ terms on this page: Beatmatching · Phrase · Bar · Downbeat · Beatgrid · Pitch fader · Pitch bend · Time signature · Trainwreck · Four-on-the-floor · Full glossary