FAQ

What does the cents reading mean?

A cent is one hundredth of a semitone. The gauge shows how far your frequency sits from the nearest in-tune note: within ±5 cents it reads in tune, beyond that it says sharp or flat. It is the standard unit for fine tuning.

What temperament does PitchSense use?

Twelve-tone equal temperament, using the formula shown at the bottom of the page: f(n) = A4 · 2^((n − 69) / 12), where n is the MIDI number. Just intonation and historical temperaments are not offered.

Which A4 values are available?

Buttons for 440, 442, 443, 415 and 432 Hz, and a field for any other value. 440 Hz is the modern standard; many orchestras tune a little higher (442 Hz, and 443 Hz in many German and Austrian orchestras), baroque ensembles use 415 Hz, and some producers prefer 432 Hz. Changing A4 re-derives every note, harmonic and table value.

Why did a link open at a different A4?

The link carried its own A4 (a4= in the address). It applies to that visit only; your saved A4 is not changed. See Share or bookmark a readout.

How accurate are the conversions?

Exact. They use the equal-temperament formula at full floating-point precision. The converter shows cents to 0.1 and frequencies to two decimals; the reference table shows four.

Which EQ band is my frequency in?

The nearest ISO 1/3-octave centre, and which fader that is on a 31-band graphic EQ, counted from 20 Hz. See The engineer's view.

Which temperature is the wavelength for?

The one shown next to it. The speed of sound rises with temperature — about 343 m/s at 20 °C — so a wavelength is only meaningful with its temperature.

How accurate is the microphone tuner?

It uses the same pitch detector as BPM Forge's tuner. On clean test tones it reads the right note within a cent from a 5-string bass's low B (31 Hz) up to A6 (1760 Hz), and names notes up to about 3 kHz; higher pitches show above range. It shows whole cents. A real microphone and room add error, and phone microphones weaken notes below about 80 Hz, so hold the phone close to the source. It is a quick check, not a strobe tuner. See Name a note from the microphone.

Should I tune my instrument with PitchSense?

You can, but the tuner in BPM Forge is made for it: instrument presets, drop tunings, a strobe view and a reference tone. PitchSense is the engineer's calculator.

Does my microphone audio leave the device?

No. The audio is analysed inside your browser; it is not recorded, stored or uploaded. Stopping the tuner or hiding the tab releases the microphone.

What does the harmonic series show?

The first eight partials of the fundamental you type — ×1 to ×8 — each with its frequency, nearest note and cents deviation. It explains why an overtone lands off a piano note: the 7th partial is about 31 cents flat.

Which languages does PitchSense speak?

The 11 platform languages. German uses German note names — H is the international B — and a setting switches any language to Do-Ré-Mi names.

What does the tool remember?

Your settings, such as the A4 reference, the wave shape and the volume. They are stored on the device and, when you are signed in, synced to your account. The frequency, note and harmonic you typed are not stored — they live in the page URL instead, see Share or bookmark a readout.

Can I search the table by flats?

Yes. The search matches sharps and flats in either spelling: C#4, Db4, F♯ and Eb all work, as do MIDI numbers and the start of a frequency.

Is it free?

Yes. PitchSense is one of the free tools on Squaresmile Tools. It opens with a free account — no card, no subscription.