Side by side
Centerline vs GuitarTuner.io
Both stand on musical tuner apps. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Free plan AndroidiPhoneMac
Centerline offers core chromatic and guitar tuning for free, with offline use and on-device audio analysis. Its stated range has limits for piano and low bass notes, and chord measurement is not provided by All Strings.
Visit Centerline Free plan AndroidiPhoneMac+2
GuitarTuner.io offers tuning in the browser, with offline use after installation and caching. The proposed native Pro app is not available to buy; the browser tuner is free without an account or upgrade.
Visit GuitarTuner.ioThe facts
| Centerline | GuitarTuner.io | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | Not published | Not published |
| Runs on | Android, iPhone, Mac | Android, iPhone, Mac, Web, Windows |
| Lowest paid plan | Centerline Complete: $3.99, paid once | GuitarTuner Pro (proposed): $4.99, paid once |
| Plans published | 2 | 2 |
| Maker | Not published | Not published |
| Website | centerlinetuner.com | guitartuner.io |
| On musical tuner apps | #4 of 32 | #8 of 32 |
Centerline: what it does well
- Chromatic mode covers 62–800 Hz.
- Four chromatic display views, including six-second pitch history.
- Guitar mode includes automatic string detection.
- Tuning works offline and audio stays on-device.
- No ads or account system.
What to know first
- All Strings does not measure a chord at once.
- Chromatic mode omits the full piano range.
- Chromatic mode omits a bass guitar’s lowest notes.
- No trial; the optional unlock is a one-time purchase.
GuitarTuner.io: what it does well
- Lists 69 free tuners across several instrument types
- Custom tunings allow any number of strings and notes
- Works offline after installation and caching
- Includes chord diagrams, audio playback, and a metronome
What to know first
- Requires a modern browser and microphone
- Pro native app is not yet available to buy
Alternatives to Centerline Alternatives to GuitarTuner.io The whole list