GuitarTuner.io
guitartuner.io
What it is
GuitarTuner.io is a free browser tuner for acoustic and electric guitar and bass. It listens through a device microphone, detects pitch in real time, and indicates whether a note is sharp, flat, or in tune; audio is processed in the browser. The site lists 69 free tuners spanning standard, drop, open, modal, bass, ukulele, mandolin, banjo, and extended-range tunings, and users can create custom tunings with any number of strings and notes. The tuner can be installed as a Progressive Web App through a browser, without an app-store download, and works offline once installed and cached. A modern browser and microphone are required. The site also offers an interactive chord library with diagrams and audio playback, plus a metronome with adjustable tempo, time signatures, and visual feedback. The browser tuner requires no account or paid upgrade. A proposed native iPhone and Android Pro app is only a demand test and is not available to buy.
Spec sheet
- What it does
- GuitarTuner.io is a browser tuner that uses a device microphone for real-time guitar, bass and other string-instrument tuning.Read 15 Oct 2026 · guitartuner.io
- Purpose
- GuitarTuner.io is a free online tuner that uses a browser microphone to tune acoustic guitar, electric guitar, and bass.Read 30 Sep 2026 · guitartuner.io
- Support
- The contact page gives hello at guitartuner dot io and links to the creator's Twitter and GitHub accounts.Read 15 Oct 2026 · guitartuner.io
- Maker
- The site identifies John Sorrentino as its creator.Read 30 Sep 2026 · guitartuner.io
- Account requirement
- The browser tuner is presented as usable without an account or paid upgrade.Read 15 Oct 2026 · guitartuner.io
- Affiliate disclosure
- The tuning directory discloses commission-based links to Guitar Tricks and says the commission does not increase the user's cost.Read 15 Oct 2026 · guitartuner.io
- Analytics and hosting
- Google Analytics and Netlify are identified as third-party services used for usage analysis, hosting and content delivery.Read 15 Oct 2026 · guitartuner.io
- Audio processing
- The site says microphone audio is processed in the browser to provide tuning feedback.Read 30 Sep 2026 · guitartuner.io
- Chord categories
- The chord library includes major, minor, seventh, suspended, power and barre chord groups.Read 15 Oct 2026 · guitartuner.io
- Chord library
- The chord library provides interactive diagrams, multiple chord variations and audio playback.Read 15 Oct 2026 · guitartuner.io
- Company details
- The opened maker pages identify the creator but do not state a headquarters or founding year.Read 30 Sep 2026 · guitartuner.io
- Cookies
- Cookies are used for visitor tracking and preferences such as favorite tunings and custom settings.Read 15 Oct 2026 · guitartuner.io
- Creator
- Official pages identify John Sorrentino as the creator.Read 15 Oct 2026 · guitartuner.io
- Creator employer
- The GitHub profile lists XSELL Technologies.Read 15 Oct 2026 · github.com
- Creator GitHub activity
- The profile shows 136 stars, 92 followers and 24 accounts followed.Read 15 Oct 2026 · github.com
- Creator location
- John Sorrentino's public GitHub profile lists Chicago, Illinois.Read 15 Oct 2026 · github.com
- Creator repositories
- The GitHub profile shows eight repositories.Read 15 Oct 2026 · github.com
- Custom tunings
- Users can create custom setups with any number of strings and notes.Read 15 Oct 2026 · guitartuner.io
- Favorites
- Favorite tunings can be starred for quick access and are stored as local preferences.Read 15 Oct 2026 · guitartuner.io
- Installable web app
- The tuner is a Progressive Web App that can be installed from a browser without an app store download.Read 30 Sep 2026 · guitartuner.io
- Instrument support
- Dedicated pages cover guitar, bass, five-string bass, six-string bass, baritone ukulele, low-G ukulele and standard ukulele tuning.Read 15 Oct 2026 · guitartuner.io
- Limit: microphone environment
- The product's own instructions say stable readings depend on a quiet room, one clear string and muting nearby strings.Read 15 Oct 2026 · guitartuner.io
- Limit: native apps
- There is no purchasable native iPhone or Android app; only a proposed $4.99 lifetime concept is shown.Read 15 Oct 2026 · guitartuner.io
- Limit: offline preparation
- Offline use depends on first loading or installing the web app so its assets can be cached.Read 15 Oct 2026 · guitartuner.io
- Local audio processing
- The privacy policy says microphone audio is processed locally with Web Audio APIs and is not recorded, stored or transmitted.Read 15 Oct 2026 · guitartuner.io
- Local storage
- Favorite tunings, custom configurations and interface preferences are saved in the browser's local storage.Read 15 Oct 2026 · guitartuner.io
- Metronome
- The metronome offers adjustable tempo, multiple time signatures and visual feedback.Read 15 Oct 2026 · guitartuner.io
- Microphone dependency
- Tuning requires browser microphone permission; the tuner cannot function without that permission.Read 15 Oct 2026 · guitartuner.io
- Native app availability
- The proposed native Pro apps are explicitly described as a demand test with nothing available to purchase.Read 15 Oct 2026 · guitartuner.io
- Native app status
- A native iPhone and Android Pro app is only a demand test and is not yet available to buy.Read 30 Sep 2026 · guitartuner.io
- Offline operation
- The installable web app is described as working offline after it has been installed or cached.Read 15 Oct 2026 · guitartuner.io
- Offline use
- The install page says the app works offline once installed and cached.Read 30 Sep 2026 · guitartuner.io
- Pitch detection
- The tuner detects pitch in real time and indicates whether a note is sharp, flat or centered in tune.Read 15 Oct 2026 · guitartuner.io
- Practice tools
- The site also offers a chord library with interactive diagrams and audio playback, plus a metronome with adjustable tempo, time signatures, and visual feedback.Read 30 Sep 2026 · guitartuner.io
- Progressive web app
- Installation is done from Safari or Chrome as a Progressive Web App rather than through an app store.Read 15 Oct 2026 · guitartuner.io
- Related favicon code
- The creator's profile includes a public JavaScript repository named favicon.js for producing ICO favicons from HTML5 Canvas.Read 15 Oct 2026 · github.com
- Related public code
- The creator's profile includes a public JavaScript repository named center.js described as an HTML5 Canvas text-icon and logo library.Read 15 Oct 2026 · github.com
- Supported devices
- The maker lists iPhone, Android, Windows, Mac and Chromebook devices with a modern browser and microphone.Read 15 Oct 2026 · guitartuner.io
- Tuning coverage
- The site lists 69 free tuners covering standard, drop, open, modal, bass, ukulele, mandolin, banjo and extended-range tunings.Read 15 Oct 2026 · guitartuner.io
- Tuning options
- The site lists 69 free tuners across standard, drop, open, modal, bass, ukulele, mandolin, banjo, and extended-range tunings.Read 30 Sep 2026 · guitartuner.io
Plans and prices
Free web tuner Free free forever browser tuner · no account · no paid upgrade · microphone required Read 15 Oct 2026 · guitartuner.io
GuitarTuner Pro (proposed) $4.99, paid once Lifetime Proposed native iPhone and Android app; demand test only; nothing to buy yet Read 30 Sep 2026 · guitartuner.io
GuitarTuner Pro (proposed) $4.99, paid once lifetime native iPhone and Android app concept · demand test only · not available to buy Read 15 Oct 2026 · guitartuner.io
Strong points and limits
Strong points
- 69 tuners cover a wide range of instruments and tunings.
- Custom tunings allow any number of strings and notes.
- Installed app can work offline after caching.
- Browser tuner needs no account or paid upgrade.
- Includes chord diagrams and a metronome.
Limits
- A modern browser and microphone are required.
- Native iPhone and Android Pro app is not available to buy.
- Offline use requires installation and caching.
Who it suits
GuitarTuner.io suits players who want to tune guitars or bass in a browser, including those who need alternate or custom tunings. Its chord library and metronome may also suit people practicing on supported devices.
GuitarTuner.io in depth
Read the full write-up
Overview
GuitarTuner.io is a browser-based tuner for guitar and bass players who want alternate setups without installing a native app. It is a strong fit for players who value tuning variety and no-cost access; those who need a conventional mobile app should look elsewhere for now.
Key features
Broad tuning choice
Its 69 free tuners span standard, drop, open, modal, bass, ukulele, mandolin, banjo and extended-range options. That range is useful for players who switch instruments or tunings, and custom tunings can use any number of strings and notes. Real-time pitch detection marks a note sharp, flat or in tune, giving direct feedback while adjusting strings.
Practice tools
The chord library pairs interactive diagrams with audio playback, while the metronome provides adjustable tempo, time signatures and visual feedback. These make the site a handy practice companion as well as a tuner, though its described tools are not a replacement for a broader lesson or recording app.
Browser and offline use
Microphone audio is processed in the browser. The Progressive Web App can be installed from a browser without an app-store download; offline use works after installation and caching. A modern browser and microphone are required, so this is less suitable where browser access or microphone permissions are a problem.
Pricing
Free web tuner costs nothing, billed Free forever. It includes the browser tuner, with no account or paid upgrade required. That removes cost and signup friction, while leaving the experience tied to the browser rather than a native app.
GuitarTuner Pro (proposed) is priced at $4.99, paid once, billed Lifetime, for a proposed native iPhone and Android app. It is currently only a demand test, with nothing to buy yet; the price is not a present purchasing option.
Platforms
The service lists Android, iOS, macOS, web and Windows. Its install guidance also names Chromebook devices, provided they have a modern browser and microphone. Phone access is through the browser-installable web app today; the proposed native iPhone and Android app is not yet available.
Who it's for
Choose GuitarTuner.io if you want a free tuner with many alternate and custom tunings, plus simple tools for practice. It particularly suits players who use less common tunings or multiple stringed instruments. If native-app access is essential, the browser-based tuner may not fit; the proposed Pro app cannot yet fill that gap.
The site identifies John Sorrentino as its creator. It also says it earns a commission, at no extra cost to users, when they sign up for its linked Guitar Tricks offer.
Pros and cons
Pros: 69 free tuning options and custom tunings accommodate a wide range of instruments and setups.
Pros: No account or paid upgrade is needed, and the installed, cached web app can work offline.
Pros: Chord diagrams, playback and a configurable metronome add practical practice support.
Cons: Tuning depends on browser microphone access and a modern browser.
Cons: The native iPhone and Android app remains a proposal, not a purchasable upgrade.
Alternatives
DaTuner is the Android choice if you prefer a tuner app with a free tier and a Premium option that removes ads and adds features; its free version has ads and fewer features.
ChromTuner suits readers who want a chromatic browser tuner with an LED meter, or a free iPhone app. Centerline is another option for Android, iOS or macOS users who want chromatic tuning and multiple display views, with a one-time Complete plan.
Fender Tune is a free Android or iOS tuner app; Tune Plus requires a Fender account. insTuner is worth considering for iOS or macOS users seeking instant-tuning mode and a tone generator in its free tier.
JustATuner is a free alternative for Linux, macOS and Windows. Pitched Tuner is an Android or iOS option with a free, ad-supported tier and a Pro upgrade for creating and saving custom tunings and temperaments.
Bandmate Chromatic Tuner offers a free Android, iOS and web alternative without third-party ads. Browse the Musical Tuner Apps list for more choices.
Verdict
GuitarTuner.io is an easy recommendation for players who want broad tuning coverage and useful practice tools without paying or creating an account. Its main limitation is that mobile use remains browser-based: choose another tuner if you need a native phone app today.
Verdict
The browser tuner is free and supports a broad selection of tunings, including custom setups. The proposed native Pro app is not yet available to purchase.
Where Specifiction places it
- Musical Tuner Apps#1 of 329.1
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