Music Tools

Free music theory and production calculators that run entirely in your browser — BPM to delay and reverb time, note frequency, chord and key transposer, capo key, scale and chord finder, circle of fifths, cents and tuning, time signature, song length, tempo markings, pitch shift and audio file size. No accounts, nothing uploaded.

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Note ↔ Frequency

Convert a musical note to its frequency and find the nearest note for any frequency.

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Metronome

Keep time with an adjustable BPM and accented downbeats.

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BPM Tap Tempo

Tap a button or the spacebar to find the tempo in BPM.

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Music Interval Calculator

Get semitones, cents, ratio and interval name between two notes.

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BPM to Delay & Reverb Time Calculator

Convert BPM into delay and reverb times in milliseconds for every note value, plus straight, dotted, triplet and LFO Hz rates.

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Song Key & Chord Transposer

Transpose a chord chart up or down by semitones or to a target key, keeping suffixes and slash bass notes, respelled with sharps or flats.

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Guitar Capo Key Calculator

Find the sounding key from a capo position and chord shape, or the capo fret and easiest open shape needed to play in any target key.

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Audio File Size Calculator

Estimate audio file size for uncompressed WAV/PCM or compressed MP3/AAC, plus data rate and how long a memory card can record.

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Scale & Chord Note Finder

Show the notes, scale degrees and diatonic chords of any major, minor, modal, pentatonic or blues scale from a chosen root.

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Cents & Frequency Ratio Calculator

Convert between cents, frequency ratios and detune in Hz — get cents from two frequencies, a ratio from cents, or a detuned pitch.

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Circle of Fifths & Key Signature Finder

Pick any major or minor key and instantly see its sharps or flats, altered notes, relative key and neighbouring dominant and subdominant keys.

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Time Signature & Bar Duration Calculator

Enter a time signature and tempo to get the exact length of one bar in seconds, plus beat duration, bars per minute and how many bars fit a given length.

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