A tuner for
recordings, not strings
Every note in a recording is measured against the A=440 grid. PitchPeek folds those distances into one distribution, finds where the mass actually sits, and reports the reference the recording was made at. A 432 Hz upload and a 440 Hz one are far apart in those terms; finer distinctions it shows you in cents so you can judge them yourself.
The needle and the cents line show direction and distance — "+8¢ sharp", "−31¢ flat", or "on the grid" when it lands where it should.
Once the reading locks, one click retunes the tab's audio to your reference in real time, so you can play along without retuning your instrument. Click again to restore the original.
Orchestra tunes to 442? Set anything from 430 to 450 Hz. Every reading — and every correction — re-baselines to it.
It listens first,
then commits
Tuning doesn't drift.
So it converges.
Tempo can legitimately change across a song, so GroovePeek keeps re-reading. A recording's tuning reference doesn't — it was fixed when the record was cut. PitchPeek treats it that way: it accumulates evidence from every second of audio into one growing picture, and once enough has integrated it locks and stops moving, unless later evidence decisively contradicts it. Integrating over the whole song is also what beats the second-to-second jitter you'd get from any single window.
The reading is content-dependent. Instruments produce overtones that don't sit on the equal-tempered grid — a fifth harmonic lands about 14 cents flat of one — so in sparse or overtone-heavy passages those partials can pull the estimate a little off the true reference. Expect roughly ±13 cents on real material, sometimes more on sparse recordings.
That's good enough to separate a 432 Hz recording from a 440 Hz one with confidence, and to answer "why does this sound flat?". Distinctions smaller than that — 440 against 442, say — sit inside the margin, so read the cents and treat them as an indication rather than a verdict. It is not a substitute for a hardware tuner on a single sustained note.
Some material has no tuning reference to find at all — percussion, spoken word, field recordings, heavily processed sound. Rather than sit on a spinner forever, PitchPeek now says so: once it has integrated a full stretch of audio and still cannot place the pitch, it reports no clear pitch and stops pretending to still be working. That is a different statement from the margin above — not “this reading may be a few cents off” but “there is not enough tonal content here to measure”.
For anyone playing
along with a recording
Found out the hard way that the track is a semitone-ish off? Now you know by how much — and you can pull it back instead of retuning.
Ensembles tune to 442 or 443 as often as 440. Set your reference and read every recording against it.
Tape transfers and old masters drift. A quick read tells you whether a rip was pitched correctly.
Plenty of uploads claim to be retuned. This tells you whether they actually are.
Your privacy, protected
PitchPeek analyzes the tab's audio in memory and discards it. Nothing is recorded, uploaded, or tracked. The only things kept on your machine are your theme choice and your reference pitch. Pitch correction changes what you hear in that tab, and only while you have it turned on.
Read the full privacy policy →What's this tuned to?
Install PitchPeek and find out in seconds.
Add to Chrome — it's freeWant the tempo instead? Meet GroovePeek →