Convert BPM to milliseconds and Hz for every note value from 1/1 to 1/64, straight, dotted and triplet, plus suggested reverb pre-delay and decay times and tap tempo.
A quarter note (1/4) lasts 60,000 ÷ BPM milliseconds. At 120 BPM that is 500 ms; at 128 BPM, 468.75 ms; at 140 BPM, 428.57 ms. Each note value is half the previous one: 1/8 lasts 250 ms at 120 BPM, 1/16 lasts 125 ms and 1/64 lasts 31.25 ms. A dotted note adds half its value and equals 1.5 times the straight one, so a dotted 1/8 is 375 ms. A triplet splits the value in three and equals 2/3 of the straight one: a 1/8 triplet lasts 166.67 ms. Setting the delay to these values makes the repeats land on the grid of the music instead of fighting it. The same number works as the period of an LFO: 500 ms equals 2 Hz, and the table shows the value in Hz and in samples (22,050 samples at 44.1 kHz, 24,000 at 48 kHz) for plugins and DAWs that ask for those formats. The Reverb tab suggests three pre-delays (1/64, 1/32 and 1/16) and five decays that end on grid points. These suggestions are mixing rules of thumb, not a standard, and your ear decides. To find the tempo of a song, press the Tap button or use the BPM detector.
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title="BPM Delay and Reverb Calculator"
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<a href="https://jkit.tools/en/tools/bpm-delay-time-calculator">BPM Delay and Reverb Calculator</a>
Divide 60,000 by the BPM to get the length of a quarter note in ms. For other note values, multiply by 4 and divide by the denominator: at 120 BPM, 60,000 ÷ 120 = 500 ms for 1/4, 250 ms for 1/8 and 125 ms for 1/16.
| Note | Straight | Dotted | Triplet |
|---|---|---|---|
| 1/1 | |||
| 1/2 | |||
| 1/4 | |||
| 1/8 | |||
| 1/16 | |||
| 1/32 | |||
| 1/64 |