Free online tools for learning and practicing music theory. From metronomes to scale finders, everything you need to improve your musical knowledge.
Steady clicks from 20–300 BPM in 2/4 to 7/8, with an accented downbeat and live beat-duration readouts.
Pick a root note and scale type to see every note in the scale, spelled out with its interval from the root.
Select the notes you are playing and get the chord name — triads, sevenths, and extended jazz voicings.
Build rhythm patterns on a visual step sequencer, add swing, and play them back to internalize any time signature.
Generate melodies inside any key and scale when you need a starting idea, then reshape them into your own.
Build chord progressions in any key from proven patterns like I–V–vi–IV, or assemble your own sequence.
Enter two notes and get the exact interval between them — major, minor, perfect, augmented, or diminished.
Music theory stops being abstract the moment you can test it. These 7 free tools let you do exactly that: enter two notes and see the interval between them, stack three notes and get the chord's name, set a tempo and hear where your timing drifts. Every answer appears instantly, in the browser — no sign-up, no download, nothing to install.
Last updated: October 23, 2026 · Written by the Pitch Detectors Editorial Team
These free music theory tools turn scales, chords, intervals, rhythm, and melody into questions you can answer by ear and eye: find any scale in any key, name a chord from its notes, build a progression, measure an interval, drill timing against a metronome, or generate a melody when the page is blank. Everything runs in your browser — no sign-up, no downloads.
Definition: Music theory tools are interactive utilities that visualize and calculate the building blocks of music — scales, intervals, chords, progressions, rhythm, and melody. Instead of memorizing patterns from a book, you select notes or settings and see the theory respond instantly.
They serve two jobs. For learners, they turn abstract rules ("a major scale is whole-whole-half-whole-whole-whole-half") into something you can see and hear. For working musicians, they are quick references: confirming a chord name mid-arrangement, checking an interval before writing it down, or generating a progression to break writer's block. The router table below matches the question in your head to the one tool that answers it.
Online Metronome — a precise digital metronome with adjustable tempo, time signatures, and accent patterns for practice.
Scale Finder — pick a root note and a scale type (major, natural minor, Dorian, pentatonic, and more) to see every note in the scale, each note's interval from the root, and the pattern laid out visually.
Chord Identifier — select the notes you are playing and get the chord name, from plain triads to extended and altered jazz voicings.
Rhythm Pattern Maker — build custom rhythm patterns on a visual step sequencer with playback and a swing control, for internalizing time signatures and syncopation.
Melody Generator — generate melodies inside any key and scale when you need a starting idea to react to.
Chord Progression Generator — create progressions in any key from common patterns, or build custom ones chord by chord.
Interval Calculator — enter two notes to get the exact interval between them: major, minor, perfect, augmented, or diminished, with the semitone count.
| Your question | Use this tool |
|---|---|
| What notes are in this scale or key? | Scale Finder |
| What chord am I playing? | Chord Identifier |
| What is the distance between two notes? | Interval Calculator |
| What chords fit this song's key? | Chord Progression Generator |
| I need a melody idea to start with | Melody Generator |
| Help me feel this rhythm or time signature | Rhythm Pattern Maker |
| Keep my practice tempo honest | Online Metronome |
Learn the tools in dependency order: intervals, then scales, then chords, with rhythm running in parallel from day one. Each layer is built from the previous one, so this sequence never asks you to use a concept you have not already met.
Western music splits each octave into 12 equal semitones. "Equal" means each step multiplies frequency by the same ratio — the twelfth root of 2 (about 1.0595). That single rule generates every scale, chord, and interval on this page.
| Interval | Semitones | Frequency ratio | Example |
|---|---|---|---|
| Minor 2nd | 1 | 1.0595 | E → F |
| Major 2nd | 2 | 1.1225 | C → D |
| Minor 3rd | 3 | 1.1892 | A → C |
| Major 3rd | 4 | 1.2599 | C → E |
| Perfect 4th | 5 | 1.3348 | C → F |
| Tritone | 6 | 1.4142 | C → F♯ |
| Perfect 5th | 7 | 1.4983 | C → G |
| Minor 6th | 8 | 1.5874 | C → A♭ |
| Major 6th | 9 | 1.6818 | C → A |
| Minor 7th | 10 | 1.7818 | C → B♭ |
| Major 7th | 11 | 1.8877 | C → B |
| Octave | 12 | 2.0000 | C → C |
Count semitones between any two notes and you have the interval — that is exactly what the Interval Calculator does. A major scale is the pattern 2–2–1–2–2–2–1 semitones; a natural minor scale is 2–1–2–2–1–2–2. Memorize those two patterns and you can spell any major or minor scale from any starting note.
The circle of fifths arranges the 12 keys in a ring where each step moves up a perfect fifth (7 semitones). Moving clockwise adds one sharp to the key signature; moving counterclockwise adds one flat. It is a key-signature calculator disguised as a diagram.
Two facts make it practical. First, relative minors: every major key shares its key signature with the minor key 3 semitones below it (A minor is the relative minor of C major — no sharps or flats in either). Second, adjacent keys on the circle share 6 of 7 scale notes, which is why modulating to a neighboring key sounds smooth. When the Chord Progression Generator suggests chords, it is drawing from exactly this neighborhood logic.
Chords are stacks of thirds taken from a scale. Take C major's scale (C–D–E–F–G–A–B), pick every other note starting on C, and you get C–E–G: a C major triad. Start on D instead and you get D–F–A: D minor. Add one more third and you get seventh chords (C–E–G–B = Cmaj7).
This explains the Chord Identifier's answers: C–E–G–B♭ is a dominant seventh because the seventh is flattened. The same stacking explains chord progressions: in any major key, the chords built on scale degrees 1, 4, and 5 are major (C–F–G in C major), degrees 2, 3, and 6 are minor, and degree 7 is diminished. The I–V–vi–IV progression that underpins countless pop songs is just degrees 1, 5, 6, and 4 of that system. Here is the full pattern for one major key and its relative minor:
| Scale degree | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|
| C major | C | Dm | Em | F | G | Am | B° |
| A minor | Am | B° | C | Dm | Em | F | G |
Read the columns vertically: the same 7 chords serve both keys, in a different order. That is why the Chord Progression Generator asks for a key first — the key fixes this menu of chords before any pattern is chosen.
A metronome marking of 120 BPM means 120 quarter-note beats per minute — one beat every 0.5 seconds. Subdivisions multiply the note rate: eighth notes at 120 BPM arrive twice per beat (4 notes per second), sixteenth notes four times per beat (8 notes per second). That is why fast passages feel exponentially harder — the note rate doubles with each subdivision level.
Practical method: set the Online Metronome to half your target tempo and play the passage as eighth notes against quarter-note clicks; when it feels easy, raise the tempo 5 BPM at a time. For odd meters like 7/8, set an accent pattern (for example 3+2+2) so the click teaches the grouping, not just the pulse. DJs working the other direction — finding a track's tempo — can tap it out with the BPM Tap Tempo tool.
Beginners get a visual, forgiving way into theory: see the scale, hear the rhythm pattern, check the chord — no notation required.
Self-taught players fill gaps methodically: the Interval Calculator settles "is this a sixth or a seventh?" arguments with bandmates in seconds.
Songwriters use the progression and melody generators as idea engines, then refine by ear.
Teachers get no-install classroom demos of scales, intervals, and rhythm that run on any student laptop or phone.
| These tools | Theory textbooks | A teacher | |
|---|---|---|---|
| Cost | Free | $20–$60 | $30–$100+/hour |
| Feedback | Instant answers | None (self-check) | Personalized correction |
| Best for | Quick answers, visualization, practice | Deep systematic study | Technique, ears, accountability |
| Weak at | Judgment, context, style | Interactivity, sound | Availability, cost |