The delay time formula converts a song’s tempo in beats per minute (BPM) into milliseconds. It helps you set a delay repeat to a quarter note, eighth note, dotted note, triplet or another musical subdivision.
For the broader timing chart and practical plugin workflow, see the delay time guide. This page focuses on the formulas and calculations themselves.
The basic delay time formula
The duration of one quarter note is:
Quarter-note delay (ms) = 60,000 ÷ BPM
The number 60,000 comes from converting one minute into milliseconds:
60 seconds × 1,000 milliseconds = 60,000 milliseconds
Because BPM means beats per minute, dividing 60,000 by BPM gives the duration of one beat, normally treated as a quarter note in a standard 4/4 tempo grid.
Worked example at 120 BPM
To calculate a quarter-note delay at 120 BPM:
60,000 ÷ 120 = 500 ms
Therefore:
- Quarter note = 500 ms
- Eighth note = 250 ms
- Sixteenth note = 125 ms
- Dotted eighth note = 375 ms
Use the delay calculator when you want an instant conversion without calculating manually.
Formulas for common note values
Let Q represent the quarter-note delay:
Q = 60,000 ÷ BPM
Then:
| Note value | Formula | Result from Q |
|---|---|---|
| Whole note | Q × 4 | 4Q |
| Half note | Q × 2 | 2Q |
| Quarter note | Q × 1 | Q |
| Eighth note | Q ÷ 2 | 0.5Q |
| Sixteenth note | Q ÷ 4 | 0.25Q |
| Dotted quarter | Q × 3 ÷ 2 | 1.5Q |
| Dotted eighth | Q × 3 ÷ 4 | 0.75Q |
| Quarter-note triplet | Q × 2 ÷ 3 | 0.6667Q |
| Eighth-note triplet | Q ÷ 3 | 0.3333Q |
Plugin labels can vary, so confirm whether a control uses straight, dotted or triplet subdivisions.
BPM to milliseconds examples
| BPM | Quarter note | Eighth note | Dotted eighth | Quarter triplet |
|---|---|---|---|---|
| 60 | 1,000 ms | 500 ms | 750 ms | 666.7 ms |
| 80 | 750 ms | 375 ms | 562.5 ms | 500 ms |
| 100 | 600 ms | 300 ms | 450 ms | 400 ms |
| 120 | 500 ms | 250 ms | 375 ms | 333.3 ms |
| 128 | 468.8 ms | 234.4 ms | 351.6 ms | 312.5 ms |
| 140 | 428.6 ms | 214.3 ms | 321.4 ms | 285.7 ms |
| 160 | 375 ms | 187.5 ms | 281.3 ms | 250 ms |
| 180 | 333.3 ms | 166.7 ms | 250 ms | 222.2 ms |
Rounded values are usually suitable for a plugin setting, although the exact decimal may be useful for precise timing.
How to calculate any delay subdivision
Step 1: Confirm the BPM
Use the project tempo or measure the song if the BPM is unknown. If the track changes tempo, one fixed delay value will not remain synchronized throughout.
Step 2: Calculate the quarter note
Divide 60,000 by the BPM. This gives the duration of one beat in milliseconds.
Step 3: Apply the subdivision multiplier
Multiply or divide the quarter-note result according to the note value. For example, multiply by 0.75 for a dotted eighth or by 2/3 for a quarter-note triplet.
Step 4: Enter the value in the delay plugin
Enter the result in milliseconds or choose the equivalent synchronized note value. Check the plugin’s tempo-sync mode before comparing the two.
Step 5: Listen in context
Formula accuracy does not guarantee that the chosen subdivision fits the phrase. Check the repeat against vocals, drums, chords and section changes.
Delay formula for tempo-synced production
Tempo sync is useful when repeats should reinforce the groove. Common choices include:
- Quarter notes for spacious, obvious echoes.
- Eighth notes for rhythmic movement.
- Dotted eighths for syncopated patterns.
- Sixteenths for short texture or thickening.
- Triplets for a contrasting three-part feel.
Use the BPM reverb sync guide when delay timing is being considered alongside reverb decay or pre-delay.
Delay formula versus reverb timing
The delay formula calculates the spacing between distinct repeats. Reverb decay describes how long a blended reflection field remains audible. Reverb can reference musical timing, but it does not need to reach zero exactly on a beat.
For a detailed comparison of the two effects, read reverb versus delay.
When to use a non-synced delay time
Not every delay should follow BPM. Free-time settings are useful for slapback, offset echoes, sound design and expressive timing that intentionally sits outside the grid.
Choose a non-synced value when the desired result is based on distance, feel or texture rather than rhythmic repetition. Keep feedback and filtering under control so the repeat does not conflict with the next phrase.
Common calculation mistakes
Dividing by BPM without converting to milliseconds
The formula uses 60,000, not 60, when the result needs to be in milliseconds. Using 60 gives seconds instead.
Confusing eighth and dotted-eighth values
An eighth note is half of a quarter note. A dotted eighth is three-quarters of a quarter note, so the two repeats fall at different rhythmic positions.
Forgetting triplet multipliers
Triplet values do not use the same multipliers as straight divisions. Use 2/3 of a quarter note for a quarter-note triplet and 1/3 for an eighth-note triplet.
Ignoring tempo changes
A fixed millisecond setting becomes unsynchronized when the song tempo changes. Update the value or use a tempo-aware delay mode.
Assuming the formula chooses the best sound
The formula gives accurate timing, but the best audible choice depends on the phrase, arrangement, feedback, filtering and mix level.
Frequently asked questions
What is the formula for delay time in milliseconds?
Use 60,000 ÷ BPM for a quarter-note delay in milliseconds. Apply a note-value multiplier for other subdivisions.
What is the delay time at 120 BPM?
At 120 BPM, a quarter note is 500 ms, an eighth note is 250 ms, a dotted eighth is 375 ms and a quarter-note triplet is about 333.3 ms.
How do I calculate dotted-eighth delay?
Calculate the quarter note first, then multiply it by 3/4: dotted eighth = (60,000 ÷ BPM) × 0.75.
How do I calculate triplet delay?
Calculate the quarter note, then multiply by 2/3 for a quarter-note triplet or divide by 3 for an eighth-note triplet.
Does delay always need to match BPM?
No. BPM matching is useful for rhythmic repeats, but free-time delay can create slapback, offset echoes and creative textures.