Free · no login · nothing uploaded
Semitone calculator.
Semitones, cents, pitch‑fader percent and frequency ratio are one quantity written four ways. Change any of them and the other three follow — plus what it does to the tempo, and whether your deck can even reach it.
Change any one of them and the other three follow, because they are the same quantity. The one that is not linear is the percent: a semitone is +5.946% going up and −5.613% going down. Not a rounding difference — a ratio and its reciprocal are not symmetrical, which is why pitching a record up and back down by the same fader amount does not return it.
What it does to the tempo
becomes
135.6
BPM — +7.6
That is what happens with key lock off. Turn it on and the tempo moves without the pitch, which is the whole point of it — but the two are the same control and you only get one. Change one without the other.
Can you reach it on the fader
| Range | Reach | In semitones | Notes |
|---|---|---|---|
| CDJ / XDJ, default | yes | ±1.01 | What the fader is set to out of the box. |
| CDJ / XDJ, ±10 | yes | ±1.65 | One press of the range button. |
| CDJ / XDJ, ±16 | yes | ±2.57 | Two presses. Past here key lock starts to sound like key lock. |
| Technics 1200, ±8 | yes | ±1.33 | The turntable standard, and the reason ±8 feels like "a lot" to anyone who learned on vinyl. |
| Turntable, ±16 mod | yes | ±2.57 | A modified or modern deck. |
The line worth remembering: a CDJ on its default ±6% reaches exactly one semitone and no more. Up a semitone is 5.946%, which leaves 0.054% of fader travel spare; two semitones needs 12.25% and is a range button away. Nothing on the deck marks where that boundary is.
Where the key lands
1 semitone up moves the Camelot number 7 positions clockwise, and leaves the letter alone. A track in 8A comes out in 3A, where the catalog holds 17,554 tracks. Do it from your own key.
Reference pitch throughout is A4 = 440 Hz, which is what every DJ mixer, CDJ and synth is tuned to. Every note in hertz
The table
Every semitone, four ways.
Note that the up and down columns are not the same number. That is not rounding.
| Interval | Up | Down | Cents | Ratio | A track at 128 becomes |
|---|---|---|---|---|---|
| 1 semitone | +5.946% | −5.613% | 100 | 1.05946 | 135.6 BPM |
| 2 semitones | +12.246% | −10.910% | 200 | 1.12246 | 143.7 BPM |
| 3 semitones | +18.921% | −15.910% | 300 | 1.18921 | 152.2 BPM |
| 4 semitones | +25.992% | −20.630% | 400 | 1.25992 | 161.3 BPM |
| 5 semitones | +33.484% | −25.085% | 500 | 1.33484 | 170.9 BPM |
| 6 semitones | +41.421% | −29.289% | 600 | 1.41421 | 181.0 BPM |
| 7 semitones | +49.831% | −33.258% | 700 | 1.49831 | 191.8 BPM |
| 12 semitones | +100.000% | −50.000% | 1200 | 2.00000 | 256.0 BPM |
Twelve semitones is an octave, which is why the ratio column ends at exactly 2.00000 and the tempo at exactly double. The whole of equal temperament is that one constraint: twelve equal multiplications that land on 2.
What the range buys you
What each pitch range actually reaches
±6% is an abstraction until it is a number of records.
| Range | From 128 BPM | In semitones | Tracks in reach | Share of the catalog |
|---|---|---|---|---|
| ±6% | 120.3 – 135.7 BPM | ±1.01 | 253,368 | 56.9% |
| ±10% | 115.2 – 140.8 BPM | ±1.65 | 322,248 | 72.4% |
| ±16% | 107.5 – 148.5 BPM | ±2.57 | 358,042 | 80.4% |
Reading that as a mixing decision: the default ±6% on a CDJ covers roughly a semitone in each direction and reaches a band of tempos around whatever you are playing. Widening to ±16 more than doubles the span and starts to make key lock audible as key lock — the artefacts of stretching audio are proportional to how far you stretch it.
Which is the honest argument for not pitching much at all. A record that needs 8% to fit is a record that did not fit; finding one that does is a better move than stretching one that does not.
Frequently asked
Common questions
How many percent is one semitone?+
Going up, 5.946%. Going down, 5.613%. They are different because pitch is a ratio rather than an addition: up a semitone multiplies by 1.0595, and down a semitone divides by it, which is multiplying by 0.9439. The two are not symmetrical, and that is why pitching a record up 6% and then down 6% does not return it to where it started.
Can a CDJ pitch a track by a whole semitone?+
Yes, and only just. Going up a semitone needs +5.946% and going down needs −5.613%, so the default ±6% covers both — with 0.054% of travel to spare at the top. What it cannot do is two semitones, which needs 12.25% and means pressing the range button. ±10 gets you to one and a half, ±16 to two and a half. Nothing on the deck marks any of those boundaries, which is what the table on this page is for.
How many cents in a semitone?+
A hundred, by definition. The cent exists so that pitch differences too small to name as intervals still have a unit — a tuner showing +12 cents is telling you something is an eighth of a semitone sharp. Twelve hundred cents make an octave.
Does changing the pitch change the tempo?+
On a turntable or with key lock off, yes, and by exactly the same ratio — that is what a pitch fader does, it plays the record faster or slower and everything moves together. With key lock on the tempo changes and the pitch does not, because the software is stretching the audio in time rather than resampling it. The two are the same control and you get one or the other.
What is a frequency ratio?+
The number every other value on this page is a way of writing. Up a semitone is a ratio of 1.05946, which is the twelfth root of two — twelve of them multiplied together give exactly 2, which is an octave. Everything about equal temperament follows from that one choice.
Explore
Key transposer · Pitch & tempo · Key & BPM changer · BPM compatibility · Note frequency chart · Half-time & double-time · All tools
Find tracks you do not have to pitch
DJ terms on this page: Pitch fader · Key lock · Camelot key · BPM · Harmonic mixing · Full glossary