Happy Birthday
The most-performed song on Earth — and public domain since 2016, so here's the real tune, every note of it, plus why that big leap is so hard to sing.
The chords & what each one does
Chords labelled with their Roman numeral(the chord's role in the key) and its job. Numbers, not letters — so you can move the whole thing to any key.
Why it works
It's a waltz: 3/4 time, one chord per bar, starting on a two-note pickup (“hap-py”).
Three phrases start identically — then the third leaps a whole octave (“happy BIRTH-day dear…”). That jump is the hardest note to sing in any song people actually sing.
Harmonically it's the eternal trio I–IV–V7: learn it in C, then move the same relationship to any key.
Structure
Public domain since the 2016 settlement: the interactive lesson has the whole tune note-for-note in first position, with the chord to strum marked under every bar.
Hear it & see it on the fretboard
Open the interactive tool and its Learn a Song tab to hear these chords, watch them light up on the neck, and play the progression in time. Want to check a key by ear? Try the key finder, and brush up on chord progressions.
More song breakdowns
Educational analysis only. We don't reproduce lyrics, sheet music or recordings — chord progressions, keys and scales are shared facts of music theory. Song and artist names are used for identification and commentary; ThunderFret is not affiliated with or endorsed by any artist.
Reading only gets you so far — open the interactive fretboard and watch these ideas light up on guitar and piano.
Enter the toolFrequently asked
Is Happy Birthday copyrighted?
No — a 2015–2016 US court case and settlement confirmed the song is in the public domain, so it can be taught and performed freely.
What chords does Happy Birthday use?
C, F and G7 (I, IV and V7 in C major) — one chord per bar in 3/4 time.
What key is Happy Birthday in?
Any key you can sing it in! Our guitar arrangement uses C major, which keeps the whole melody in open position.