Reference table of musical note frequencies across all octaves in Hz with A4 calibration.
Note Frequency Chart turns an A4 tuning reference into a table of pitches and frequencies across octaves. Set the calibration, then read the hertz value beside the required note and octave. The values follow the repeating octave relationship: the same note one octave higher has twice the frequency, while semitone steps are multiplicative rather than equal-sized additions in hertz. The common surprise is that the gap in hertz grows at higher pitches, even though each adjacent pair remains one semitone apart.
A concrete input and expected output from the current implementation.
Input
A4 calibration: 440 Hz; look up A5
Expected output
A5: 880 Hz
A5 is one octave above A4. An octave doubles frequency, so 440 x 2 = 880 Hz.
Use A4 as the anchor for the entire chart. At 440 Hz calibration, a note n equal-tempered semitones from A4 has frequency 440 x 2^(n/12) Hz; with another calibration, replace 440 with that A4 value. Calibration changes are therefore proportional across every octave and pitch class, rather than a fixed number of hertz added to each row.
Read the note name and octave number together, since a bare letter does not identify one frequency. Moving to the same note in the next octave doubles its value, and moving to the previous octave halves it. The octave label changes at C in scientific pitch notation, so B3 and C4 are adjacent semitones even though their octave numbers differ.
No. A4 is the tuning anchor, so changing it rescales every note in the table by the same ratio. Moving from 440 Hz to 442 Hz multiplies every displayed frequency by 442/440. It does not add 2 Hz to every note; only A4 itself changes by exactly 2 Hz.
No, not by itself. The chart supplies reference frequencies but does not measure an audio signal. First use a tuner or frequency analyzer to estimate the fundamental, then compare that value with the chart. A strong overtone may be louder than the fundamental, and bent or vibrato notes may move between listed values.
The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.
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