Free BPM Counter for Any Song, by File or by Tapping

What BPM means, and how to read the result

BPM (beats per minute) is a song’s tempo: how many beats fit into one minute. At 120 BPM a beat falls every half second, and at 60 BPM once a second. The beat is the pulse you nod your head or tap your foot to.

The finder shows the tempo to one decimal place. A reading such as 127.9 or 128.1 on a dance track usually means the producer set the project to 128, since software tempos are usually whole numbers. A live band recording can sit at 96.4, because a drummer playing without a click track does not lock to a grid.

BPM counts beats, and the time signature says how those beats group into bars. A song at 90 BPM in 4/4 has four beats per bar, and a waltz at 90 BPM in 3/4 has three, so the waltz’s bars go by faster at the same tempo. Songs in 6/8 are usually counted in two beats per bar, so the BPM you tap will often be a third of the eighth-note count.

How the analyzer finds the tempo

The analyzer first builds an onset strength curve, a line that jumps wherever a new sound starts: a kick, a snare hit, a strummed chord. It then runs autocorrelation, comparing that curve with delayed copies of itself to find the delay at which the pattern repeats most strongly. That delay is the beat length, and the BPM is 60 divided by it in seconds. The result is then refined to 0.1 BPM.

The search covers 60 to 200 BPM, the range that holds the beat of most popular music. A song with tempo changes gets the dominant tempo, the one that runs through most of the track, so a ballad that speeds up for its last chorus reports its main tempo.

The same analysis also reports the key with its Camelot code. For what those mean and which songs mix together, see the key finder.

Half-time and double-time readings

A beat pattern repeats at several levels at once. A trap beat is often programmed at 140 BPM while its kick and snare move at a heavy half-time 70. Both numbers describe the same song, and a listener, a DJ app and a streaming database can each pick a different one.

That is why the finder shows the half-time and double-time readings next to the main BPM. To choose, tap on every kick and snare hit of the main groove. In most pop, rock and hip-hop the kick falls on beats one and three and the snare on two and four, so those taps mark the beat. The reading that matches your taps is the tempo you feel. If the main reading falls outside the genre’s usual range below, its half or double usually falls inside it.

Very slow or very fast music sits outside the 60–200 search range. A 50 BPM ballad is likely to show as 100 with 50 in its half-time slot, and a 220 BPM punk song as 110 with 220 as its double.

Typical tempos by genre

These are the ranges producers and DJs usually work in. Genres overlap, and a single song can sit outside its genre’s range.

The “felt as” column matters when you mix across styles. A 140 BPM dubstep track and a 70 BPM hip-hop beat can share a grid, because the dubstep kick and snare already move at 70.

Italian tempo markings in BPM

Classical scores often mark the tempo with an Italian word. The BPM ranges below are approximate, since metronome makers and editions draw the lines in slightly different places.

Orchestral and piano recordings often bend the tempo for expression, which is called rubato. The analyzer gives the dominant tempo of such a piece, and individual phrases will move around it.

Tapping the tempo accurately

Tap tempo divides one minute by the average gap between your taps. It averages the last eight intervals, so a single early or late tap only nudges the number, and it resets after two seconds without a tap.

1. Start the song from a verse with drums. Intros and breakdowns often have no clear beat.
2. Listen for a bar before tapping, then tap on the kick and snare. Hi-hats often run two or four times faster than the beat.
3. Tap the button, or press Space or T on a keyboard.
4. Keep tapping for at least nine taps, which fills the eight-interval average, and watch the number settle.
5. If you lose the beat, stop for two seconds and start again. The count begins fresh.

Counting the tempo with a stopwatch

Without any tool, count beats while a stopwatch runs, then work out BPM = beats counted × 60 ÷ seconds. Twenty-three beats in 10 seconds is 23 × 60 ÷ 10 = 138 BPM.

Longer counts are more precise. Over 15 seconds each beat is worth 4 BPM, so one missed beat moves the result by 4. Over 30 seconds a beat is worth 2 BPM, and over a full minute the count is the BPM.

When the reading looks wrong

Most odd readings come from the music itself. These are the usual causes and what to do about each.

• Half or double of what you expected. Check the half-time and double-time readings and tap along to decide which one you feel.
• A number with a decimal on a live recording. A drummer playing without a click track speeds up and slows down slightly, and the finder reports the average. For a DJ set, set the grid by ear around that value.
• A song that changes tempo. The finder reports the dominant tempo. For the BPM of one section, tap along to that section.
• Swing and shuffle. Swung eighth notes make the pulse harder to pin down, and a reading can land on a related value. Tapping on the kick and snare gives the tempo musicians would count.
• Little or no beat. Ambient pieces, drones and solo voice give the analyzer few onsets to measure, so the result is a guess. Tap where you feel the pulse instead.
• A sped-up or slowed-down version. Tempo scales with speed, so a nightcore edit or a slowed version reads at a different BPM from the original.

Using the tempo in a mix or a project

Beatmatching two tracks

To blend two songs, a DJ brings them to the same BPM. The change in speed, as a percentage, is the target BPM divided by the original BPM, minus one, times 100. Taking a 125 BPM track to 128 is 128 ÷ 125 = 1.024, a 2.4% speed-up, inside the ±8% range of a classic turntable pitch fader.

Speed changes pitch too, unless the software has key lock switched on. A 5.9% change moves the music by a semitone, so a 2.4% push raises it by less than half a semitone. Check that the keys still fit with the Camelot wheel. Mixxx, a free DJ app, analyzes BPM and key for a whole library and has key lock.

Tracks also line up at half or double tempo. An 87 BPM hip-hop track fits under a 174 BPM drum and bass track, because every other drum and bass beat lands on a hip-hop beat. Look at the half-time and double-time readings when you search for pairs like these.

Delay times from the tempo

A delay set to a note length repeats in time with the groove. One beat lasts 60,000 ÷ BPM milliseconds, and the other note values follow from that.

Many delay plugins can also sync to the host tempo, which does this math for you. The roundup of delay plugins compares the ones that do.

Tempo after a speed change

Changing a song’s speed multiplies its BPM by the same factor. A 120 BPM song played at 85% runs at 102 BPM, the usual move behind a slowed and reverb edit, and a 128 BPM track sped up to 125% for nightcore lands at 160. To change the tempo while keeping the pitch, see how to change speed, tempo and pitch in Audacity.

Cutting video to the beat

Video editors place cuts on beats, and the tempo tells you how many frames each beat lasts: frames per beat = frame rate × 60 ÷ BPM.

When a beat is not a whole number of frames, counting a rounded number of frames from cut to cut drifts off the music. At 128 BPM and 24 fps, 11 frames per beat falls behind by more than a second each minute. Place each cut by its timeline position, or snap it to markers set on the beat, and the error never builds up.