Softonic

BPM Finder

Loading the audio analyzer...

Find the likely tempo of a song, loop or rehearsal recording without tapping it out by hand. Choose an audio file and the BPM Finder analyzes repeating rhythmic pulses to return an estimated beats-per-minute value plus useful half- and double-time alternatives. Use the result to set a metronome, align a DAW grid, plan a remix or compare tracks. Tempo perception can be ambiguous, so treat the number as a starting point and confirm it by listening, especially for live performances, changing tempos, sparse arrangements or syncopated music.

How to find BPM from an audio file

  1. 1

    Choose a clear audio file

    Select a song, loop or recording. A section with steady drums or other distinct attacks usually provides stronger tempo evidence than silence or sustained pads.

  2. 2

    Let the browser prepare the excerpt

    The browser decodes the file locally and, for longer recordings, automatically analyzes a centered excerpt. Codec support depends on the browser and encoding, not only the extension.

  3. 3

    Analyze the repeating pulse

    The tool measures onset-like energy changes and tests how regularly they repeat within the selected BPM range.

  4. 4

    Compare tempo candidates

    Read the strongest estimate, clarity label and related half- or double-time pulse levels instead of assuming one metrical level is always correct.

  5. 5

    Confirm and save the result

    Check that the pulse stays aligned through several phrases, then copy the BPM or download a JSON or CSV analysis summary.

What BPM measures

BPM means beats per minute. A tempo of 120 BPM contains 120 perceived beats in one minute, so each beat is 0.5 seconds apart. BPM describes the rate of the pulse; it does not identify the key, time signature, downbeat, groove or exact drum pattern.

The basic conversions are:

  • seconds per beat = 60 ÷ BPM
  • milliseconds per beat = 60,000 ÷ BPM
  • BPM = 60 ÷ seconds per beat
  • samples per beat = sample rate × 60 ÷ BPM
  • In 4/4 only, seconds per four-beat bar = 240 ÷ BPM
Tempo Seconds per beat Milliseconds per beat Four-beat bar
60 BPM 1.000 s 1,000 ms 4.000 s
90 BPM 0.667 s 667 ms 2.667 s
120 BPM 0.500 s 500 ms 2.000 s
128 BPM 0.469 s 469 ms 1.875 s
140 BPM 0.429 s 429 ms 1.714 s

The bar calculation assumes four counted beats per bar. Do not use it as proof that a track is in 4/4. Ableton’s interactive lesson on beats and tempo demonstrates how the pulse rate relates to BPM.

How audio tempo estimation works

A browser-based analyzer first reads the selected file and decodes it into PCM sample data with the Web Audio API. It can then examine changes in energy or other onset-like events and test how regularly those changes repeat. Strong repeating periods become tempo candidates, which can be expressed in BPM.

That process estimates a perceived tempo from the sound. It does not read the tempo field from a DAW session, MIDI file, score or commercial music database. Music-information-retrieval evaluations commonly account for more than one plausible tempo because listeners may tap to different metrical levels in the same excerpt. The MIREX Audio Tempo Estimation task documents evaluation with alternate tempo candidates.

How to interpret the result

Result Meaning How to use it
Estimated BPM Strongest global tempo candidate Start here when setting a metronome or DAW grid
Half-time Estimated BPM ÷ 2 Try this when the result feels twice as fast as the musical pulse
Double-time Estimated BPM × 2 Try this when the result feels half as fast as the counted subdivisions
Clarity How consistently periodic evidence supports the leading candidate Use it for comparison, not as a guaranteed accuracy percentage
Analyzed interval Section of decoded audio used for the estimate Check that it contains an established, representative rhythm

A clarity label does not mean “95% accurate.” It describes separation and consistency within this analysis and is not calibrated as a probability against every genre or recording condition.

Why half-time and double-time answers happen

A rhythm can support several related pulse levels. One listener may nod on every kick at 70 BPM while another counts eighth-note motion at 140 BPM. Both rates describe the same two-to-one rhythmic relationship. Tempo researchers often call this an octave error, even though it concerns rhythm rather than pitch.

Use musical context to decide:

  • Choose the rate that matches the beat you would naturally tap.
  • Check whether a metronome stays aligned through several bars.
  • Compare the result with the arrangement, but do not use genre ranges as proof.
  • In a DAW, place the first clear downbeat on the grid and inspect later phrases for drift.

When the estimate may be unreliable

Audio characteristic What may happen Better approach
Steady drums and repeated attacks Usually produces clearer periodic candidates Analyze a representative rhythmic section
Long silence or quiet intro Silence weakens useful evidence Trim the file so an established rhythm falls near the center
Ambient, legato or percussion-free music Few distinct attacks may exist Tap the pulse manually with Tap Tempo on the Metronome
Swing, syncopation or polyrhythm Subdivisions may outrank the expected pulse Compare half- and double-time candidates by ear
Live playing or rubato Tempo may drift throughout the recording Treat one BPM as an average or inspect separate sections
Deliberate tempo changes A single global value hides the changes Export separate trimmed sections and analyze each one
Very short clips Too few repeated cycles may be present Use a longer excerpt containing several phrases
Noise, clipping, applause or speech Non-musical attacks may influence the pattern Choose a cleaner section when possible

Automatic BPM analysis is a practical aid, not a substitute for listening. A numerically stable candidate can still represent the wrong metrical level.

Browser processing, formats and privacy

The selected audio is read through the browser’s File API and decoded with decodeAudioData(). Browser codec support varies, so the same filename extension does not guarantee decoding everywhere. WAV is the most dependable interchange choice; conventional MP3, M4A, AAC, OGG or FLAC files work only when the current browser supports their encoding.

The audio bytes, filename, waveform and extracted features remain in browser-local state and are not bound to Livewire or sent to an external analysis service. Normal page requests still occur when the page loads or funnel steps change. Local storage may preserve bounded analysis data between funnel steps; reset the project to remove it.

Copying and exporting a result

  • Copy BPM copies the primary numeric estimate.
  • Copy summary includes the estimate, related pulse levels, duration, interval and clarity label.
  • JSON preserves the structured analysis values for a custom workflow.
  • CSV provides a spreadsheet-friendly table of candidates and timing values.

These downloads are analysis summaries, not audio exports. The tool does not alter, retime, transcode, fingerprint or identify the selected recording.

Frequently Asked Questions

BPM means beats per minute: the number of regular pulses counted in 60 seconds. At 120 BPM, one beat occurs every 0.5 seconds. It describes tempo, not key, time signature or rhythmic pattern.

Accuracy depends on the recording and on what a listener considers the main pulse. Steady, percussive music is generally easier than rubato, ambient, noisy, syncopated or changing-tempo material. Confirm the estimate with a metronome or DAW grid.

The analyzer may have selected a related metrical level. A pattern perceived at 70 BPM can often also support a 140 BPM count. Compare the half- and double-time candidates and choose the pulse you naturally tap.

Yes. Live performances can drift, expressive music can speed up and slow down, and productions can contain deliberate tempo changes. A global estimate summarizes the analyzed interval and may hide local changes.

The tool accepts files that the current browser can decode through Web Audio. Codec support can vary even when two files share an extension. If decoding fails, try PCM WAV or a conventional MP3 or AAC export.

Use enough material for several repetitions of the established rhythm. A clean chorus or drum-led section is usually more informative than a very short hit, silent intro or transition. Longer is not always better when the song changes tempo.

No. The selected file is decoded and analyzed in this browser. The audio, filename, waveform and extracted analysis features are not sent through Livewire or to an external audio or AI service.

No. Tempo, musical key and meter are separate properties. Use Song Key Finder when you know the chords, and verify meter by listening or consulting a score. A four-beat timing calculation does not prove 4/4.

Related Tools

Mouse Tester

Test your mouse buttons, wheel scrolling, pointer movement and double-click timing in the browser. See event logs and movement samples without uploads.

Competition Bracket Maker

Build a seeded or shuffled single-elimination bracket for 2–32 teams or players, assign automatic byes, advance winners, copy and print it.

Metronome

Practice with a precise online metronome. Set BPM, meter, accent and subdivisions, then play a steady browser click locally.

Fancy Serial Number Checker

Check US-style currency serial numbers for fancy patterns like radars, ladders, repeaters, low numbers and star notes.

Baby Name Generator

Generate baby name ideas filtered by gender, origin, first letter, length and style. Fresh lists every click; save favourites to compare.

Blossom Solver

Enter the centre letter and six petal letters to find every valid Blossom answer. Sorted by length and highlighted for pangrams.