Boneyard Tools

Cents Interval Calculator

Enter two frequencies to find the interval between them in cents, along with the pitch ratio and the equivalent number of semitones. There are 1200 cents in an octave and 100 cents per semitone.

How to use the cents calculator

  1. Enter the first frequency in hertz, the reference pitch.
  2. Enter the second frequency to compare against it.
  3. Read the interval in cents, the pitch ratio and the semitone count.

Examples

An octave

440 Hz to 880 Hz
1200 cents (12 semitones)

One semitone

440 Hz to 466.16 Hz
100 cents (1 semitone)

Frequently asked questions

How are cents calculated between two frequencies?

Cents equal 1200 times the base-two logarithm of the ratio of the two frequencies, that is 1200 x log2(f2 / f1). An octave is 1200 cents.

How many cents are in a semitone?

There are 100 cents in an equal temperament semitone, so 1200 cents fill an octave of twelve semitones. The calculator also reports the interval as a semitone count.

What does a negative cents value mean?

A negative value means the second frequency is lower than the first. The interval still has the same size, just measured downward instead of upward.

Why use cents instead of hertz for intervals?

Cents describe the perceived size of an interval regardless of pitch, while a hertz difference sounds larger at low frequencies than at high ones. Cents make intonation comparisons fair.

How precise is a cent?

A cent is a hundredth of a semitone and is near the limit of what most listeners can hear. Tuners often aim for within a few cents of the target pitch.

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