🎚️ Music BPM to Delay Milliseconds & LFO Rate Calculator
Calculate audio delay time in milliseconds (ms), reverb pre-delay, and LFO frequency in Hz for whole, half, quarter, 8th, 16th, dotted, and triplet notes.
| Note | Straight | Dotted | Triplet | Hz (straight) |
|---|---|---|---|---|
| 1/1 Whole | 2000.0 ms | 3000.0 ms | 1333.3 ms | 0.500 |
| 1/2 Half | 1000.0 ms | 1500.0 ms | 666.7 ms | 1.000 |
| 1/4 Quarter | 500.0 ms | 750.0 ms | 333.3 ms | 2.000 |
| 1/8 Eighth | 250.0 ms | 375.0 ms | 166.7 ms | 4.000 |
| 1/16 Sixteenth | 125.0 ms | 187.5 ms | 83.33 ms | 8.000 |
| 1/32 Thirty-second | 62.50 ms | 93.75 ms | 41.67 ms | 16.00 |
The dotted eighth is the famous one. At 120 BPM that is 375.0 ms — the setting behind the rhythmic guitar delay on a lot of eighties records. It works because a dotted eighth is three sixteenths, so the repeats land between the beats rather than on them.
For reverb, a pre-delay of a sixteenth (125.0 ms) keeps the tail out of the way of the transient, and setting the decay near a bar length (2000.0 ms) stops it smearing into the next one. For an LFO, the hertz column is the rate to dial in when your synth has no tempo sync.
Dotted values are 1.5× the straight note; triplets are two thirds, so three of them fill the space of two. These are the mathematically exact times — a delay pedal or plugin will round to whatever resolution its controls have, and some analogue delays drift with temperature.
What Music BPM to Delay Milliseconds & LFO Rate Calculator Does
A beat at 120 BPM lasts 500 milliseconds, because there are 60,000 milliseconds in a minute. Everything else follows from dividing or multiplying that: an eighth note is half of it, a sixteenth a quarter, a dotted note one and a half times, a triplet two thirds.
Those numbers are what you dial into a delay, a reverb pre-delay, a gate or an LFO when the device has no tempo sync — and plenty of good hardware and older plugins do not. Getting it right is the difference between an effect that locks to the groove and one that fights it.
The dotted eighth is the one worth knowing by heart. At 120 BPM that is 375 ms, and it is behind a great deal of rhythmic guitar delay because a dotted eighth is exactly three sixteenths — the repeats land between the beats rather than on them, filling the gaps instead of doubling what is already there.
The same arithmetic runs in reverse. If a delay setting sounds right and you want to know what tempo it implies, dividing 60,000 by the milliseconds gives it back, which is a fast way to match a new part to a sample or loop you did not make.
How to Use Music BPM to Delay Milliseconds & LFO Rate Calculator
- Enter musical tempo in BPM (Beats Per Minute) or select a genre preset
- Review quarter note millisecond delay time and LFO rate in Hz
- Inspect the complete note division table (Half, 8th, 16th, Dotted, Triplet)
Formula Used by Music BPM to Delay Milliseconds & LFO Rate Calculator
Beat length, and every division of it
quarter note (ms) = 60,000 ÷ BPM · dotted = ×1.5 · triplet = ×2⁄3 · Hz = 1000 ÷ ms
- dotted
- a dot adds half the note's value again — a dotted eighth equals three sixteenths
- triplet
- three notes in the space of two, so each is two thirds the length
- Hz
- the same figure as a frequency, for LFO rates on synths without tempo sync
Worked example
120 BPM.
- Quarter note: 60,000 ÷ 120 = 500 ms
- Eighth: 250 ms. Sixteenth: 125 ms
- Dotted eighth: 250 × 1.5 = 375 ms
- Eighth triplet: 500 ÷ 3 = 166.67 ms
Result: A bar of 4/4 is 2,000 ms, and a quarter-note LFO runs at 2 Hz.
Delay times in milliseconds
Common tempos, straight values.
| BPM | 1/4 | 1/8 | 1/8 dotted | 1/16 |
|---|---|---|---|---|
| 90 | 666.67 | 333.33 | 500.00 | 166.67 |
| 100 | 600.00 | 300.00 | 450.00 | 150.00 |
| 120 | 500.00 | 250.00 | 375.00 | 125.00 |
| 128 | 468.75 | 234.38 | 351.56 | 117.19 |
| 140 | 428.57 | 214.29 | 321.43 | 107.14 |
| 174 | 344.83 | 172.41 | 258.62 | 86.21 |
Where each division tends to get used
| Setting | Typical division | Why |
|---|---|---|
| Rhythmic guitar delay | 1/8 dotted | Three sixteenths, so repeats fall between the beats |
| Slapback | 60–120 ms, not synced | Short enough to read as a thickening rather than a repeat |
| Vocal throw | 1/4 or 1/2 | Long, sparse repeats that do not clutter the line |
| Reverb pre-delay | 1/16 or 1/32 | Keeps the tail clear of the transient |
| Reverb decay | around one bar | Stops the tail smearing into the next bar |
| Tremolo or filter LFO | 1/8 or 1/16 in Hz | Use the hertz column when the synth has no sync |
How to Read Your Result
Feedback and time interact
A long delay with high feedback fills the mix quickly. As a rough starting point, the longer the delay the less feedback it can carry before the repeats stack into mud — and a high-cut filter on the repeats keeps them behind the source rather than competing with it.
Triplets and dotted notes are opposites
A dotted note stretches the division and a triplet compresses it, so they pull the feel in opposite directions. Dotted values push against the grid and create the illusion of a faster part; triplets create a rolling, swung feel against straight material.
Not everything should be in time
Slapback and doubling effects work precisely because they are not locked to the grid — the ear reads them as one thickened sound rather than as a repeat. Anything under about 120 ms is usually better set by feel than by arithmetic.
These are exact; your gear is not
Delay controls often move in coarse steps, and analogue units drift with temperature and voltage. Set the tempo-synced value where the device allows it, and use these numbers as the target when you are dialling by hand.
Limitations & Accuracy Notes
- Assumes a constant tempo. Music with tempo changes or heavy rubato needs the value recalculated per section.
- Quarter note is treated as the beat, which holds for 4/4 and most common time signatures but not for compound meters such as 6/8, where the dotted quarter is the beat.
- Swing and shuffle are not modeled; a swung eighth is deliberately not half a quarter.
- Values are exact to the millisecond, which is finer than most hardware can be set.
- Says nothing about feedback, filtering or modulation, which matter as much as the time.
Frequently Asked Questions
How do you calculate quarter note delay milliseconds from BPM?
How are dotted and triplet delay times calculated?
How is delay time calculated from tempo?
What are dotted and triplet values?
Should reverb be timed to tempo as well?
Does this work for LFO rates?
Why does my delay still sound out of time?
Is my data stored?
References & Further Reading
- MDN — Web Audio timing — Background on audio timing in milliseconds and hertz