Looking for a clear A440 tuning reference? Play the note below and use it to tune your guitar, ukulele or Venezuelan cuatro by ear. You don’t need a tuning fork or an app to begin. You need one dependable pitch, a quiet place, and a little patience.
One distinction matters before you touch a tuning peg: A440 is the A4 note at 440 hertz. Not every instrument has an open A4 string. If you confuse octaves, you can overtighten a string. Here’s how to find the right pitch on yours.
Listen to the A440 reference tone
Play the video, then play your instrument’s matching note. Alternate between them. When the note on your instrument is a little flat, tighten its string gently; when sharp, loosen slightly. Repeat with small adjustments. If two nearby pitches produce a pulsing or wavering sound, those pulses usually slow as they approach unison. Always check the octave first.
What is A440, and which A should I tune?
A440 is the widely used reference pitch for instruments and ensembles: A4 = 440 Hz, the A above middle C. An octave lower has half the frequency, so A3 = 220 Hz and A2 = 110 Hz. All three are A notes, but they’re not interchangeable pitches.
| Instrument | Reference string | Difference from A440 |
|---|---|---|
| Standard ukulele (G-C-E-A) | Open A4 = 440 Hz | Matches the video |
| Venezuelan cuatro (A-D-F#-B) | Open A3 = 220 Hz | One octave below |
| Standard guitar (E-A-D-G-B-E) | Open A2 = 110 Hz | Two octaves below |
Never tune an open guitar or cuatro A string all the way up to 440 Hz. Instead, use the reference on the correct fret, or listen for the lower octave.
How to tune a guitar with A440
The guitar’s standard open strings, low to high, are E2-A2-D3-G3-B3-E4. Its open A string is only 110 Hz. A simpler way to use the video is to make A4 on the thin, high E string.
- Press the high E string at fret 5. That note is A4. Compare it with the video and adjust the high E string until the fretted note matches.
- Use your newly tuned open high E to tune the B string: B at fret 5 should match open high E.
- Continue downward: G at fret 4 matches open B; D at fret 5 matches open G; A at fret 5 matches open D; low E at fret 5 matches open A.
- Play a familiar chord, then check each string again.
If you aren’t sure whether you found the correct note, use our free online instrument tuner to confirm it before tightening further.
How to tune a ukulele with A440
Most standard-tuned soprano, concert and tenor ukuleles use G-C-E-A. Their open A string is A4 at 440 Hz, exactly the pitch in the video. Play that string alongside the reference and adjust slowly until they agree.
Now use the A to check the other strings. E at fret 5 sounds A4, while C at fret 4 should match the open E. On a traditional high-G ukulele, G at fret 2 also sounds A4. If yours has a low-G string, that fretted note is one octave lower. Don’t force it higher; use a tuner for the correct octave.
How to tune a Venezuelan cuatro using A440
A Venezuelan cuatro is traditionally tuned A3-D4-F#4-B3. Its open A string is 220 Hz, one octave below the A440 recording. That difference is correct, not a tuning error.
- Press the cuatro’s A string at fret 12. This gives A4, the same pitch as the video. Adjust that string carefully while comparing the fretted note. Released, the open A remains A3.
- Play A at fret 5 (D4) and match the open D string to it.
- Play D at fret 4 (F#4) and match the open F# string.
- Play A at fret 2 (B3) and match the open B string.
For a beginner-friendly check of all four open strings, visit our free Cuatro tuner, which provides the correct reference pitches.
Video reference or physical A440 tuning fork?
Both give you a fixed A4 reference. A physical metal A440 tuning fork rings when struck gently against a suitable soft surface. Hold the stem and listen near the prongs, without hitting your instrument’s finish. It provides one A note, not an automatic reading for every string.
Prefer a physical A440 reference? See our stainless-steel A440 tuning fork in the TuCuatro store. Check the current price, stock, and shipping availability for your region on the product page. The A440 video above remains free to use.
Common A440 tuning questions
Does every string need to be 440 Hz?
No. The A440 tone is a reference. Each instrument has its own open-string notes and octaves. Find those first, then use fretted notes or a chromatic tuner for the rest.
Why does my A string sound lower than the video?
It may be the correct lower octave: A3 is 220 Hz and A2 is 110 Hz. Don’t tighten the open string until it sounds identical to A4. Check the note name and octave.
Should I learn by ear or use a digital tuner?
Both. Ear practice teaches you to recognize pitch differences, while a digital tuner helps you verify the result, especially in noisy rooms. Start with the A440 reference, tune slowly, and enjoy playing.
