Music Calculators

1 Tempo and note length

How long each note lasts at a tempo, in milliseconds (ms, thousandths of a second) and seconds.

Fix the tempo above to see the note lengths.

The other way: from a note length to BPM

Which note gets the beat is your choice. The quarter note (crotchet) is the default here, as in the site's metronome; in 6/8 you may prefer to count dotted quarters. A dotted note lasts one and a half times as long as a plain one; a triplet note lasts two thirds as long (three in the time of two).

2 Delay and echo times

Delay times that land on the beat, for a delay pedal, an echo plug-in or a looper.

Fix the tempo above to see the delay times.

ms is the time between one echo and the next. Hz (hertz) is the same length given as a rate, repeats per second, the unit many tremolo and LFO rate controls use.

3 Frequency and note

Which note a frequency is, and how far from it in cents; or the frequency of any note.

Frequency to note

Note to frequency

Octave numbers are scientific pitch notation: middle C is C4 and the number goes up at every C, so the B below middle C is B3. The Helmholtz name is shown too: c′ for middle C, c for the octave below, C below that. Cents: 100 cents make one half step (semitone); a plus sign means the frequency is higher (sharp), a minus sign lower (flat). Frequencies use equal temperament from your A4.

4 Intervals, ratios and cents

The size of an interval in cents from its frequency ratio, and back; equal temperament next to just ratios.

Equal temperament (ET) and one published set of just ratios (others exist)

Cents measure interval size: 1200 cents to the octave, 100 to each equal-tempered half step. Just ratios are small whole-number frequency ratios. The ones shown are one published set, the five-limit 12-note scale in its "asymmetric" form; others exist. * marks a step where that same table also gives another ratio (shown).

5 Length of a piece

How long a number of bars (measures) lasts, or how many bars fit in a length of time.

The other way: bars in a length of time

Uses the same time signature and tempo as above, and assumes the tempo stays steady with no repeats, pauses or slowing down. Repeats count as extra bars.

6 Swara frequencies for your Sa

Sa is the home note of Indian classical music, and you choose its pitch. The other swaras (notes) are counted up from it. Pick your Sa to see where all twelve swara positions fall.

Fix Sa's frequency above to see the swaras.

ET (equal temperament) puts every half step at exactly 100 cents, like a keyboard or harmonium. Just uses small whole-number ratios to Sa; the set shown is one published five-limit set (others exist), not a rule. * Published sets disagree on these positions, and singers and players shade many swaras differently from raga to raga, so treat the just column as a reference only. Sa and Pa (3:2) are fixed once Sa is chosen.

Swara names here are Hindustani (Sa, komal Re, Re ...). Turn on Indian terms in the footer to add the Devanagari and a column of Carnatic swarasthana names (R1, R2 ...), which are labelled as Carnatic.