Works Offline
Offline Guitar Tuner for MacNo Internet. No Telemetry. No Account.
Chromatic Tuner makes zero outbound network connections. Pitch detection runs locally on your CPU, audio is processed in memory and discarded, and there's no account to create. Tune anywhere — on a plane, in a basement, on tour.
Why Offline Matters
When the Wi-Fi Goes Away, the Tuner Doesn't
Most "free" online tuners are a browser tab connected to an ad-tech graph: pageviews logged, fingerprint stored, audio passing through whatever the host site has added to the WebAudio pipeline. Offline-first means none of that surface area exists in the first place.
Chromatic Tuner makes zero outbound network connections after install. There is no telemetry, no anonymous usage stats, no crash reporter that fires home. We can prove it: open Little Snitch or Lulu, watch the app for an hour, see nothing. Your audio stream is processed in memory on the YIN time-domain algorithm and discarded — never written to disk, never sent off-device.
That matters more in some places than others. Green rooms with hostile wifi, hotel rooms behind captive portals, planes and trains, basement studios with bad reception, summer festivals where 50,000 phones are competing for the same towers. None of that touches a native app: launch, plug in, tune, done.
It also matters for trust. Sessions, rehearsals, and lessons sometimes involve material that hasn't been released yet. Knowing the tuner physically cannot leak it (App Sandbox + Hardened Runtime, no network entitlement) is a different category of guarantee than "we promise we don't."
Why a Native App
A Real Tuner, on Core Audio.
Browser tuners reroute audio through the WebAudio sandbox — 12–60 ms of jitter, silent downsampling, throttled the moment the tab loses focus. Phone tuners can't see your audio interface at all — just the built-in mic, with auto-gain and noise suppression already mangling the signal before any pitch detector touches it.
Chromatic Tuner sits directly on Core Audio. It sees your USB interface at full sample rate, runs YIN on your CPU, and the needle responds the moment you pluck.
The Meter and the Strobe.
The 31-LED bar is what you reach for when plucking — segments blend orange to green and snap to in-tune in under 50 ms.
The Peterson-style rotating strobe is the one for sustained intonation work. Bands lock inside a hard ±0.5 ¢ deadband, so "in tune" is genuinely stationary — not just close. A vintage analog needle and a minimal drifting sine wave round out the four.
What's Inside
Nine Things, Done Well.
A tuner should be on screen for fifteen seconds, do its job, and get out of your way. Everything below earns its place by that rule.
YIN Pitch Detection
A0 to C8 (27.5 Hz – 4186 Hz), accurate to ±0.14¢ on pure tones and ±1¢ in real use. Octave-error correction stops a plucked string reading an octave high.
Four Display Modes
An LED bar, a Peterson-style strobe with a hard ±0.5¢ deadband, a vintage analog needle, and a minimal drifting sine wave — one toolbar click apart.
Built-In Metronome
40–240 BPM, meters from 2/4 to 7/8, tap tempo and an accented downbeat — in its own window, so it sits open beside the tuner while you practise. Space starts it.
Instrument Presets
17 across guitar, bass and strings.
Lives in Your Menu Bar
A 360 px popover, one click away.
Reference Tones
Tap a string to hear a clean sine.
Custom A4 + Transpose
349–499.9 Hz, plus ±11 semitones.
Light, Dark, System
Follows macOS, or pin it either way.
Keyboard-First
Space starts and stops. ⌘W, ⌘Q.
Design
Lives Wherever You Need It.
A 360 px popover that drops out of the menu bar between takes. Customization tucked behind a flyout. A dock icon that earns its slot. Every surface modeled on real hardware, then matched to your system theme.
How It Works
Three Steps. The Third One Is the Only One You'll Do Twice.
- 01
Open Chromatic Tuner
Drag from the DMG to Applications. Launch from Spotlight or your menu bar. No account, no activation.
- 02
Allow Microphone Access
macOS asks once. Approve, and your default input — built-in mic, USB interface, whatever — is wired in. Audio stays on-device.
- 03
Pluck a String
The LED meter sweeps to the closest note. Amber means off, green means in. Tune until it stays green for a beat.
New in 1.2 · iPhone & Apple Watch
Also in Your Pocket.
ChromTuner: Guitar Tuner brings the same YIN engine to iOS — free. Chromatic mode, Standard E and Drop D, the LED meter and analog needle, plus a gentle haptic tap the moment a string locks in. Version 1.2 adds a metronome and string-life tracking, both on iPhone and Apple Watch. One $6.99 purchase unlocks everything else.
Free forever — no ads, no account, no subscription.
Prefer the Mac App Store? Same app, same price.
Ready When You Are
One Purchase. Forever Yours.
Today's Total
One-Time · Lifetime 1.x Updates
- Chromatic Tuner — Universal Binary (Apple Silicon + Intel)
- Lifetime 1.x Updates Included
- Direct Email Support From the Developer
After You Pay
- 1Receipt to Your Email
- 2Download Link, Valid 7 Days
- 3Drag Chromatic Tuner Into /Applications
FAQ
Questions, Answered.
Quick answers about temperaments, instruments, accuracy, and what actually runs on your Mac.
Does Chromatic Tuner Work Offline?
Yes. Chromatic Tuner runs entirely offline — no audio, telemetry, or account ever leaves your Mac. The app makes zero outbound network connections, and pitch detection runs locally on the CPU.How Is My Audio Handled — Is Anything Sent Off-Device?
Nothing leaves your Mac. The microphone stream is processed in memory and discarded — Chromatic Tuner doesn't record, save, transmit, or analyze your audio beyond pitch detection.How Is Chromatic Tuner Different From Free macOS Tuners?
Chromatic Tuner runs natively on Core Audio with sub-50 ms latency, ±1¢ YIN accuracy, no ads, no telemetry, and no account. Free tuners typically run in a browser tab (12–60 ms of WebAudio jitter) or hand the signal to a phone's built-in mic — auto-gain and noise suppression baked in before the tuner ever sees it. The $6.99 buys lifetime 1.x updates and direct email support.Does It Run on Intel Macs and Apple Silicon?
Yes — both. Chromatic Tuner is a universal binary that runs natively on Apple Silicon (M1/M2/M3/M4) and Intel Macs. macOS 14 Sonoma or later required.Do I Need an Audio Interface?
No. Chromatic Tuner uses your Mac's built-in microphone by default, and works with any USB audio interface or Aggregate Device that macOS recognizes.How Accurate Is the Tuner?
Chromatic Tuner is accurate to ±0.14 cents on pure sine tones and ±1 cent in real-world use. The in-tune zone (green) opens at ±5 cents, which is what most studio engineers consider perfect intonation. Detection uses the YIN time-domain algorithm with a 4096-sample window, octave-error correction for plucked strings, and median-of-5 + exponential smoothing for stable readings at ~22 Hz.
Ready to Tune?
Native macOS. Offline. ±1¢ accuracy. Yours for $6.99 — one-time, lifetime 1.x updates.
Buy for $6.99Specifications
The Technical Bits
| Operating System | macOS 14.0 (Sonoma) or later |
|---|---|
| Architectures | Apple Silicon (arm64) + Intel (x86_64), universal binary |
| Pitch Algorithm | YIN, 4096-sample window with 50% overlap |
| Pitch Range | A0 (27.5 Hz) → C8 (4186 Hz) |
| Accuracy | ±0.14¢ on pure sines, ±1¢ real-world |
| Update Rate | ~22 Hz |
| Latency | Sub-50 ms perceived |
| Smoothing | Median-of-5 + exponential, 70 Hz high-pass before detection |
| Audio Input | Built-in mic, USB interfaces, Aggregate Devices, hot-plug detection |
| Temperaments | 8 historical, with movable tonic for non-equal systems |
| Instrument Presets | 17 across guitar, bass, bowed strings, folk strings, chromatic — plus capo |
| File Size | ~5 MB DMG |
| Network | None — works fully offline |
| Privacy | Sandboxed, Hardened Runtime, Privacy Manifest, no telemetry |
| Updates | Lifetime updates for the 1.x line, included with purchase |
| License | Personal one-time purchase, single user |
Related