Quick answers to the most common questions about the pitch check.
It listens to a few notes from your piano and checks whether the overall pitch has drifted far enough that your tuner will likely need to do a pitch correction before the regular tuning. It's a quick heads-up so you (and your tuner) know what to expect — not a substitute for a real tuning visit.
No. This app measures one thing — how close your piano is to standard concert pitch (A=440 Hz). A real tuning is much more than that: your tuner sets roughly 230 strings against each other so chords and intervals sound right, evens out the unisons (most notes have 2 or 3 strings that have to match), and adjusts touch and tone in ways no app can do.
Use this app to give your tuner a heads-up before the visit. Don't use it as a reason to skip the visit.
Almost certainly yes. A piano can drift flat (or sharp) gradually as a whole and still sound "in tune with itself" — but being in tune with itself is not the same as being at concert pitch, or at the string tension the piano was designed to hold long-term.
The longer it sits below pitch, the more work it takes to bring back up — and the more it strains the structure to live there. Most piano makers recommend tuning at least once a year, even if it sounds OK to you.
When a piano is well off pitch, your tuner has to bring it most of the way to standard pitch first — a rough pass — and then come back and do the fine tuning. The first pass has to be rough by design: the strings won't hold their new pitch yet, so trying to tune it precisely is wasted effort until the piano settles.
More passes means more time on site, which usually means a higher fee than a standard tuning. This is exactly what this app is checking for: whether the piano is close enough that one pass will do, or far enough off that two or more will be needed.
"Cents" are how musicians measure small pitch differences — 100 cents equals one half-step (one key on the piano). A few cents off is normal between tunings. Once you're past the threshold your tuner has set in this app, you're likely in pitch-correction territory.
Either way, the next step is the same: call your tuner. Even a piano that reads "in range" here can still be due for a tuning — this app only checks pitch. It can't hear the unisons, the temperament, or the things that actually make a piano sound musical.
Pianos don't tune to perfect math. Piano strings are slightly stiff, which makes their upper harmonics drift sharp of where simple math says they should be. To compensate, tuners deliberately stretch the octaves a little — wider apart at the top, wider at the bottom — so the piano sounds in tune with itself across its full range.
This app applies a generic version of that stretch curve, so its readings sit closer to where a tuner's ear would land than a plain chromatic tuner does. A regular chromatic tuner app on your phone uses straight equal-temperament math and will show different numbers — that doesn't mean either is broken, they're just measuring against different references. Your tuner uses dedicated piano-tuning tools that go further still, building a stretch curve specific to your instrument.
Three notes spread across the middle of the piano give a much better picture than one. The middle note is the most stable; the two on either side confirm whether the whole piano is drifting in the same direction or just one section.
Both, probably. The reading depends on how cleanly you played the note, the room's background noise, your microphone, and how long the note rings. Run it a couple of times and trust the average.
If the results swing wildly, something's interfering. Try a quieter room, press the key firmly once (don't tap repeatedly), and let the note ring all the way out. If it's still inconsistent, your piano may simply need that tuning.
A few common causes:
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A working piano technician in Denver, Colorado. The app is free to use — if it was helpful, the "Buy me a coffee" button on the main screen helps keep it that way.