This free mandolin tuner shows an interactive F-style headstock and body — tap a course to target it, or let Auto mode detect it for you. Standard GDAE tuning across 4 paired courses.
RUNS ENTIRELY IN YOUR BROWSER · YOUR AUDIO IS NEVER RECORDED OR SENT ANYWHERE
Last updated: · Reviewed for accuracy against current browser APIs
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Click "Start Tuning" and allow microphone access to begin.
Start with your lowest G course, and mute the other string of the pair with your pick so the tuner hears only one.
Watch the meter.
Turn the tuning peg slowly — left means flat (tighten), right means sharp (loosen).
Tune the second string of the pair to match.
Both pegs of that course light up together once the pair is in tune with each other.
Repeat for the D, A, and E courses.
Then recheck all four courses, since tuning one pair can slightly shift the others.
How this tuner detects pitch
When you pluck a string, this tool analyzes the sound through your microphone using an autocorrelation algorithm — it compares the waveform against slightly delayed copies of itself to find the point where they line up most closely, and that lag reveals the exact frequency you're playing. This runs entirely in your browser via the Web Audio API; your microphone audio is never recorded, uploaded, or sent anywhere, and it disappears the instant you close the tab.
Troubleshooting a jumpy or inaccurate reading
The needle won't settle, or jumps between notes
Background noise is the most common cause — a fan, a TV, or other instruments ringing nearby all confuse pitch detection. Mute any strings you're not testing and play a single, clean note rather than a chord.
It picks the wrong string
In Auto mode, a string that's very badly out of tune can land closer to a neighboring string's target pitch than its own, so the tuner locks onto the wrong one. Switch to manual string selection until it's roughly in range, then Auto mode will track it correctly from there.
Nothing registers at all
Check that microphone permission was actually granted — look for a blocked-mic icon in your browser's address bar — and confirm you're playing firmly enough for the microphone to pick up a clear signal above any background noise.
Standard mandolin tuning: 4 courses, 8 strings
A mandolin's 8 strings are arranged into 4 pairs, called courses, with both strings in each pair tuned to the identical note. Standard tuning is G3, D4, A4, E5 — the exact same note names as a violin, just doubled up. Playing both strings of a course together is what gives the mandolin its distinctive bright, slightly shimmering, chorused tone.
Course
Note
Frequency
4th (thickest, lowest)
G3
196.00 Hz
3rd
D4
293.66 Hz
2nd
A4
440.00 Hz
1st (thinnest, highest)
E5
659.25 Hz
While tuning, mute the string you aren't currently working on by resting your pick or a finger lightly against it, then pluck only the one you want the tuner to hear — trying to tune both strings of a pair at once just makes for a confusing, wandering reading.
A brief history of the mandolin
The mandolin belongs to the lute family, whose roots stretch back thousands of years to early instruments found in ancient Mesopotamia, Egypt, and Greece. The mandolin reached its modern form in 18th-century Italy, where it became a defining sound of Baroque music — Vivaldi wrote several concertos for it, and both Mozart and Beethoven featured it in their operas. From there it spread widely, finding a home in Balkan and Celtic folk music, Brazilian choro, Portuguese fado, Mexican estudiantinas, and American country and bluegrass.
A-style vs. F-style mandolins
The two most common modern mandolin body shapes were both developed by Gibson in the early 1900s, applying violin-making principles to a carved-top design. The A-style has a plain, symmetrical teardrop body with a simple headstock — lighter, more affordable, and typically warmer in tone. The F-style, shown in the illustration above, adds a decorative scroll on the upper shoulder and two sharp points at the bottom of the body, along with F-shaped sound holes borrowed straight from violin design. These additions are mostly cosmetic and don't fundamentally change the tuning, though many players feel the added mass of the scroll contributes to a brighter, more cutting tone especially suited to bluegrass.
Is mandolin tuning the same as violin tuning?
The note names are identical — G3, D4, A4, E5 on both instruments — which is a big part of why mandolin and violin players can often read each other's sheet music directly without transposing anything. The difference is entirely in how each note is produced: a violin plays each note on a single string, while a mandolin doubles every note across a paired course of two strings, which is exactly what gives it that shimmering, chorused character a violin doesn't have.
Frequently asked questions
How do I tune my mandolin with this tool?
Click Start Tuning, then pluck one string of a course while muting its partner with your pick. The closest course highlights automatically, and the needle shows sharp or flat until both its pegs turn green.
What is standard mandolin tuning?
Standard mandolin tuning is G3, D4, A4, E5 — the same notes as a violin, just doubled: each note is played by a pair of strings called a course, for 8 strings total.
Why does a mandolin have 8 strings instead of 4?
The strings are arranged in 4 pairs, called courses, with both strings in a pair tuned to the same note. Playing both strings together gives the mandolin its bright, chorused, slightly shimmering tone.
How do I tune just one string of a pair?
Mute the string you aren't tuning by resting your pick or a finger against it, then pluck only the string you want the tuner to hear.
What's the difference between A-style and F-style mandolins?
A-style mandolins have a plain, symmetrical teardrop body. F-style mandolins add a decorative scroll on the upper shoulder and two points at the bottom of the body — cosmetic differences that don't change the tuning.
Is mandolin tuning the same as violin tuning?
The note names are identical, which is why mandolin and violin players can often follow each other's sheet music directly. The mandolin just plays each note as a doubled pair of strings instead of one.
How often should I tune my mandolin?
Check before every practice session, and again if you've been playing for a while, since 8 strings under tension pull on the neck more than a typical guitar and can drift more noticeably.
Can I use this tool for a mandola or octave mandolin?
No — those instruments use different tunings entirely. For anything outside standard GDAE mandolin tuning, our Chromatic Tuner listens for all 12 notes rather than a fixed set of strings.
Is my audio recorded or sent anywhere?
No. All detection happens locally in your browser using the Web Audio API. Nothing is uploaded, recorded, or stored.
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