Written by Daniel Murphy | Last updated: June 2026
What This Site Is
GuitarChordIdentifier.com is a free, browser-based tool that identifies guitar chords from physical fret and string input or from live microphone audio — and explains the interval theory behind every chord it names.
The site is built and maintained by Daniel Murphy, guitar theory educator and audio analysis developer. Every tool, every explanation, and every piece of educational content on this site is Daniel’s direct work. There are no advertisers, no sponsored recommendations, and no third-party contributors shaping what appears here.
GuitarChordIdentifier.com operates in two distinct modes: a fret input mode that identifies chords from the positions you select on a virtual fretboard, and a microphone mode that captures your guitar’s audio and performs polyphonic pitch detection to identify the chord you are playing. Both modes produce a chord name, the interval set that produced it, and — where applicable — the inversion if the bass note is not the chord root.
Why This Site Exists
Most guitarists learn chords by shape — a grip memorised by hand position rather than by name. This works until it does not: until you want to communicate a chord to another musician, understand why two chords sound good together, read a lead sheet, or figure out what that borrowed shape from a YouTube video actually is. At that point, knowing the name matters — and knowing the interval basis for the name matters even more.
The problem with most chord identifier tools is that they return a name without explanation. A result of “Gmaj7/B” is useful if you know it means G major seventh chord with B in the bass (third inversion). It is not useful if you do not know what any of that means. GuitarChordIdentifier.com names the chord and explains why — the pitch class set, the intervals, the inversion — so the result teaches you something rather than just answering the immediate question.
For the microphone mode, the challenge is more technical. Guitar chords are polyphonic — multiple notes sounding simultaneously — which means the detection pipeline must identify multiple fundamental frequencies from a single audio stream, separate each fundamental from its harmonics, and match the resulting pitch class set to a chord name. This is a genuinely hard problem in browser audio, and its accuracy limitations are documented honestly on this site. For the complete technical documentation of both pipelines, see the How It Works page.
What This Site Provides
Fret Input Chord Identification Select the fret positions and strings you are playing on the virtual fretboard. The tool extracts the pitch class set for your selected positions, analyses the intervals between notes, and looks up the matching chord name — including the inversion if the lowest note is not the root. No microphone required. No audio captured. All calculation runs locally in your browser.
Microphone Chord Identification Play a chord on your guitar near your microphone. The tool captures the audio via the Web Audio API, performs polyphonic pitch detection to extract simultaneously sounding fundamentals, maps them to pitch classes, and identifies the matching chord. Results include the chord name, detected notes, and inversion where applicable. All audio processing is local — nothing is transmitted. See the Data Security page for the full explanation.
Educational Content Articles and explainers covering guitar fretboard theory, interval analysis, chord naming conventions across classical, jazz, and pop guitar contexts, inversion identification, polyphonic pitch detection, and practical guides to using chord knowledge in real playing situations.
Accuracy and Limitations Documentation Every result and every accuracy claim on this site includes an honest account of what the identification produces and where it falls short. Fret input identification is highly reliable for standard voicings. Microphone-based identification has real limitations for complex voicings, heavily distorted tone, and ambient noise — and these are documented explicitly. The FAQ covers the most common questions about result interpretation.
Who This Site Is For
Guitarists who encounter unfamiliar chord shapes Whether you are learning from a recording, exploring the fretboard, or inheriting a chord chart with unfamiliar notation, this tool identifies what you are playing and explains the theory behind the name.
Music students learning applied guitar harmony Understanding the relationship between fret positions, pitch classes, and chord names is a foundational skill in guitar music theory. This tool makes that relationship explicit and interactive.
Songwriters and arrangers working with guitar parts Naming chords accurately — and understanding their inversions — is essential for communicating with other musicians, notating charts, and understanding why chord sequences work.
Developers and researchers working with browser-based polyphonic detection GuitarChordIdentifier.com provides documented technical reference on polyphonic pitch detection from guitar audio in a browser environment, including the accuracy challenges specific to guitar chord identification.
Accuracy and Transparency
Daniel Murphy does not publish chord formulas, interval definitions, or detection accuracy figures without traceable sources. All technical content is cross-referenced against established guitar theory literature and the W3C Web Audio API specification. Limitations are documented on every relevant page — including the Contact page, which is always the right place to report an error.
Get in Touch
contact@guitarchordidentifier.com All questions, corrections, and data requests are handled personally by Daniel Murphy.
GuitarChordIdentifier.com is an independent site with no advertising, no sponsors, and no third-party contributors. All content is written by Daniel Murphy. Last updated: June 2026.