BPM, beats per minute, is the tempo of a song: how many steady pulses happen in 60 seconds. To find it, tap along to the beat with a tap tempo tool, or count the beats for 15 seconds and multiply by 4. Either takes under a minute and gets you within a few BPM. The hard part usually isn't the math. It's deciding which pulse is "the beat," because the same song can read as 70 or 140 BPM depending on what you count. This guide covers both methods, how accurate each is, how to avoid the half-time and double-time trap, and how to turn a BPM into delay times for music production.
Method 1: Tap tempo
Tap tempo is the fastest way to measure a song's BPM:
- Play the song and listen for a few seconds until you feel the pulse.
- Tap a key or button on every beat. Most people find it easiest to tap along with the kick drum or the beat they'd clap to.
- Keep tapping steadily for 10 to 20 seconds. The reading settles as more taps are averaged.
- Round to the nearest whole number unless you need more precision.
The math behind it is simple. If you tap 8 times and 3.39 seconds pass between the first tap and the last, there are 7 gaps between taps (not 8), so the tempo is 7 × 60 ÷ 3.39 = 123.9 BPM, which rounds to 124. A good tool averages every gap, so one early or late tap barely moves the result. Counting taps instead of gaps is the classic mistake when doing this by hand: it would give 8 × 60 ÷ 3.39, which is about 142 BPM.
Tap a key or the button in time with the music and the BPM updates with every beat.
BPM Finder →Method 2: Count beats for 15 seconds and multiply by 4
No tool needed, just a timer:
- Start the song and let the first bar or two go by so you're locked into the pulse.
- Start a stopwatch on a beat and count "one" on that beat.
- Count every beat until the timer reads 15 seconds.
- Multiply by 4. Thirty beats in 15 seconds is 30 × 4 = 120 BPM.
The catch is resolution. Being off by one beat in 15 seconds shifts the answer by 4 BPM, so a count of 31 gives 124 and 32 gives 128. Counting longer reduces that error:
| Count for | Multiply by | Example | Off by one beat |
|---|---|---|---|
| 15 seconds | × 4 | 30 beats → 120 BPM | ±4 BPM |
| 20 seconds | × 3 | 40 beats → 120 BPM | ±3 BPM |
| 30 seconds | × 2 | 60 beats → 120 BPM | ±2 BPM |
| 60 seconds | × 1 | 120 beats → 120 BPM | ±1 BPM |
If you want a whole-number answer you can trust, count for the full minute, or count for 30 seconds and then confirm with tap tempo.
Half time and double time: the most common BPM mistake
A song with a pulse at 140 BPM can feel like 70 BPM if you only notice every other beat, and a slow ballad at 70 BPM can read as 140 if you tap along with the hi-hat. Neither reading is wrong in a mathematical sense; they're the same music measured at different note values. But when a DJ app, a tutorial or a sample pack lists a BPM, it usually means one specific pulse, so a reading that's exactly half or double the listed number is almost always this issue, not an error in your counting.
A few ways to settle it:
- Find the backbeat. In a lot of pop and rock, the snare lands on beats 2 and 4. If the snare lands on every one of your taps, or exactly halfway between them, you're probably counting at half speed; if there are three of your taps between snare hits, you're probably at double speed.
- Use your body. Count the pulse you'd naturally nod, clap or step to.
- Check plausibility. If you get 220 BPM for a mid-tempo song, halve it. If you get 50 for something people dance to, double it.
- Pick a convention and stick to it. For matching two songs, what matters is that you measured both the same way.
When BPM is hard to pin down
- Live recordings and older music recorded without a click track often speed up and slow down slightly. Measure a few sections and take the typical value.
- Tempo changes. Some songs switch tempo between sections. Measure each part separately.
- Free-time intros and outros. Ambient intros, rubato passages and fades may have no steady pulse at all. Skip ahead to where the rhythm settles.
- Swing and triplet feels. Swung rhythms can tempt you to tap the uneven subdivisions. Tap the main pulse, not the swung notes between beats.
Many DJ apps and music production programs can detect tempo automatically. If an automatic reading looks half or double what you hear, tap it out to check.
BPM to milliseconds: delay time chart
Once you know a song's tempo, you can set delay and reverb times so the echoes land on the beat. One beat, a quarter note, lasts 60,000 ÷ BPM milliseconds. The other note values follow from that:
- Half note: quarter note × 2
- Dotted eighth: quarter note × 0.75
- Eighth note: quarter note ÷ 2
- Eighth-note triplet: quarter note ÷ 3
- Sixteenth note: quarter note ÷ 4
All values below are in milliseconds, calculated with those formulas and rounded to one decimal place.
| BPM | 1/2 | 1/4 (one beat) | Dotted 1/8 | 1/8 | 1/8 triplet | 1/16 |
|---|---|---|---|---|---|---|
| 60 | 2,000.0 | 1,000.0 | 750.0 | 500.0 | 333.3 | 250.0 |
| 70 | 1,714.3 | 857.1 | 642.9 | 428.6 | 285.7 | 214.3 |
| 80 | 1,500.0 | 750.0 | 562.5 | 375.0 | 250.0 | 187.5 |
| 90 | 1,333.3 | 666.7 | 500.0 | 333.3 | 222.2 | 166.7 |
| 100 | 1,200.0 | 600.0 | 450.0 | 300.0 | 200.0 | 150.0 |
| 110 | 1,090.9 | 545.5 | 409.1 | 272.7 | 181.8 | 136.4 |
| 120 | 1,000.0 | 500.0 | 375.0 | 250.0 | 166.7 | 125.0 |
| 128 | 937.5 | 468.8 | 351.6 | 234.4 | 156.3 | 117.2 |
| 140 | 857.1 | 428.6 | 321.4 | 214.3 | 142.9 | 107.1 |
| 150 | 800.0 | 400.0 | 300.0 | 200.0 | 133.3 | 100.0 |
| 160 | 750.0 | 375.0 | 281.3 | 187.5 | 125.0 | 93.8 |
| 174 | 689.7 | 344.8 | 258.6 | 172.4 | 114.9 | 86.2 |
Small rounding differences between this chart and a plugin's display are normal; why conversions don't always match explains where they come from. To express a tempo as a rate instead, for a tremolo or LFO, divide the BPM by 60: 120 BPM is 2 beats per second, or 2 Hz for one cycle per quarter note.
Quick checklist
- Tap along for 10 to 20 seconds, or count beats for at least 15 seconds and multiply.
- Round to the nearest whole number unless you need more precision.
- Sanity-check for half or double time using the snare and the pulse you'd dance to.
- Measure separate sections if the song changes tempo.
Wondering whether a free browser tool is good enough for this? Free vs. paid online tools covers when a free tool does the job and when paid software earns its price.
Frequently asked questions
How do I find the BPM of a song without software?
Play the song, start a timer, and count every beat for 15 seconds. Multiply the count by 4 to get beats per minute. Counting for 30 seconds and multiplying by 2 is more accurate.
Why does my BPM reading come out half or double?
You tapped or counted a different pulse from the one the song is usually described with, such as every other beat or every eighth note. Both readings describe the same music. Pick the pulse you would naturally clap or nod along to.
How accurate is tap tempo?
It depends on how many taps you make. A tap tempo tool averages the gaps between taps, so tapping steadily for 10 to 20 seconds smooths out small timing errors much better than a few taps.
How do I convert BPM to milliseconds?
Divide 60,000 by the BPM to get the length of one beat (a quarter note) in milliseconds. At 120 BPM that is 500 ms. Halve it for an eighth note, or multiply by 0.75 for a dotted eighth.
Can a song have more than one BPM?
Yes. Some songs change tempo between sections, and live recordings without a click track often drift slightly. Measure each section separately if the feel changes.