Delay Time Calculator + Reverb Time Calculator
Use this free tool to calculate note-synced delay times and practical reverb times for your track BPM.
The Delay Time Calculator and Reverb Time Calculator help you pick fast, musical starting points for mixing.
What is a delay time calculator and how does it work?
A delay time calculator converts your track's BPM into millisecond values that sync to musical note divisions like whole notes, halves, quarters, eighths, and so on. Instead of guessing a delay time by ear, you enter your BPM and get exact ms values to dial into your delay plugin. This keeps your delay rhythmically locked to the tempo, so echoes feel musical rather than random.
How do I convert BPM to milliseconds (ms)?
The formula is: delay time (ms) = 60,000 / BPM x note division. For a quarter note at 128 BPM: 60,000 / 128 = 468.75 ms. For an eighth note, halve that to 234.38 ms. This BPM to ms calculator does the math instantly for all common note values, so you can copy the number straight into your plugin.
What is a reverb time calculator used for?
A reverb time calculator gives you BPM-aware RT60 decay targets, meaning the time it takes for a reverb tail to fade by 60 dB. Rather than setting reverb decay by feel, you get values anchored to your track's tempo: a short ambience at one quarter note, a medium room at a half note, a long hall at one bar, and an epic tail at two bars. These are practical starting points for mixing, not acoustic science.
What is pre-delay in reverb, and how do I calculate it?
Pre-delay is the gap between the dry sound and the onset of reverb. A well-chosen pre-delay keeps vocals and instruments clear before the reverb washes in. A common starting point is a 16th or 32nd note value from your BPM. At 128 BPM that's 117 ms or 59 ms. Use the delay time table above, pick the 1/16 or 1/32 row, and enter that value as your reverb plugin's pre-delay.
What's the difference between straight, dotted, and triplet delay times?
Straight delays land exactly on the beat grid. Dotted delays (1.5x the straight value) fall between beats and create a pushing, sloshy feel common in reggae and dub. Triplet delays divide beats into three and create a shuffling, swung feel common in R&B and soul. Calculating all three lets you pick the one that fits your track's pocket.
What is RT60 and why does it matter for mixing?
RT60 is the standard measure of reverb decay time, specifically how long it takes reflected sound to drop 60 dB below the original signal. In mixing, it's the target you're setting when you adjust a reverb plugin's decay knob. Longer RT60 values (1 to 4 seconds) suit halls and pads; shorter values (under 0.5 s) suit drums and tight rooms. Anchoring your RT60 targets to your track BPM ensures the tail always feels in time with the music.