Mandolin Tuner — GDAE, Octave Mandolin and the Family

A mandolin has four pairs of strings, called courses, tuned in unison to G3–D4–A4–E5 — the same notes as a violin, in fifths. The doubled strings are played together with a pick, and the pairs are what make the instrument’s characteristic tremolo possible.

How to use it

1. Start the tuner. Press Start Tuner (Microphone) and allow microphone access. The audio is analysed in your browser; nothing is uploaded.
2. Choose the right preset. The selector above carries Mandolin and Octave Mandolin — the two presets this site ships. Pick the one that matches the instrument in your hands before you play; the notes are the same letter names an octave apart, so the wrong preset will send you an octave in the wrong direction.
3. Play one course at a time. A mandolin course is two strings, so strike the pair together with the pick as you normally would, then let it ring. The display reports the strongest pitch it hears from the pair.
4. Mute the other courses. The courses share intervals and ring freely, so an open A can take over the reading while you tune the E. Rest the side of your picking hand across the other strings.
5. Tune the pair to each other, not just to the display. Get the course close with the tuner, then listen: two strings a few cents apart beat against each other, and the pulsing slows as they meet. Use the display for the target and your ears for the last few cents.
6. Turn the machine head toward the note. A needle left of centre means flat; right means sharp. Ease back below a sharp note and come up to it, which seats the string and holds its pitch more reliably.
7. Work through all four courses, then check them again. Mandolin strings are steel and light; raising one course adds tension that shifts the neck slightly, so the first course you tuned may have moved by the time you finish.
8. Use the hear-tone buttons for ear checks. Each card plays its own reference pitch, so you can match a course to the card tone and finish by ear if the room is too noisy for a good microphone reading.

Mandolin string frequencies

The cards run 4th course to 1st course, which is also low to high — the 4th course is the lowest. Every frequency assumes a reference of A4 = 440 Hz, the default on this tuner; if your ensemble tunes to another standard, choose it in the reference chips and every target scales to match.

Course	Note	Frequency (A4 = 440 Hz)
4th (lowest)	G3	196.00 Hz
3rd	D4	293.66 Hz
2nd	A4	440.00 Hz
1st (highest)	E5	659.26 Hz

Each of those cards represents two strings sounding together in unison. The interval between adjacent courses is a perfect fifth, exactly as on a violin: G to D, D to A, A to E.

Octave mandolin

The octave mandolin uses the same tuning as the mandolin, an octave lower. Wikipedia gives it as G2–D3–A3–E4, and describes its relationship to the mandolin as that of a tenor violin to a violin. It is a larger instrument with a longer scale — typically around 20 inches (510 mm) — so the strings are heavier and the courses do not feel like mandolin courses under the fingers.

Course	Note	Frequency (A4 = 440 Hz)
4th (lowest)	G2	98.00 Hz
3rd	D3	146.83 Hz
2nd	A3	220.00 Hz
1st (highest)	E4	329.63 Hz

Select Octave Mandolin in the selector to see these cards. Because the lowest course is G2 = 98.00 Hz, the display will show note names with a different octave number from the mandolin’s, even though the letters are the same.

The mandolin family and its neighbours

The plan of the family is easy to get wrong, so here is what the sources actually say, instrument by instrument. Every frequency below assumes A4 = 440 Hz.

Instrument	Tuning (low → high)	Frequency	Relationship
Mandolin	G3–D4–A4–E5	196.00 / 293.66 / 440.00 / 659.26 Hz	The soprano member; four courses
Mandola	C3–G3–D4–A4	130.81 / 196.00 / 293.66 / 440.00 Hz	A fifth below the mandolin — Wikipedia: “the same relationship as that of the viola to the violin”
Octave mandolin	G2–D3–A3–E4	98.00 / 146.83 / 220.00 / 329.63 Hz	An octave below the mandolin
Irish bouzouki	G2–D3–A3–D4 (most often)	98.00 / 146.83 / 220.00 / 293.66 Hz	Fifth-based tunings; not strictly a mandolin-family instrument

• Mandola. Wikipedia describes it as “tuned a fifth below the mandolin, in the same relationship as that of the viola to the violin”, normally tuned like a viola and a tenor banjo: C3–G3–D4–A4. It is called the tenor mandola in Britain and Ireland.
• Octave mandolin. Tuned an octave below the mandolin: G2–D3–A3–E4. In Britain and Ireland it is often called the octave mandola, and in continental Europe the word mandola may refer to this instrument rather than to the C3–G3–D4–A4 one — check which instrument a seller means.
• Bouzouki. Wikipedia’s Irish bouzouki article is explicit that the instrument is “not strictly a member of the mandolin family”, though it resembles and sits in the same range as the octave mandolin. Its fifth-based tunings are most often G2–D3–A3–D4; other tunings include G2–D3–A3–E4, which makes it function as an octave mandolin, and A2–D3–A3–D4. The Greek tetra-chordo bouzouki is a different instrument again, tuned C3–F3–A3–D4 with octave pairs on the low courses (Wikipedia’s bouzouki article). The longer 24–26 inch scale is what distinguishes the Irish instrument from an octave mandolin in theory, although the terms are often used interchangeably in practice.
• A chart for the rest of the family. The four instruments above are the ones most often asked about, and the first three are the ones the term “mandolin family” most reliably covers. If your instrument is not one of them — a mandocello, a cittern, a mandriola — read the tuning your instrument’s maker specifies and tune it string by string against the chromatic tuner at /tools/chromatic-tuner/, because this page does not carry a preset for it.

Courses, tremolo and why the pairs matter

• A course is two strings treated as one. Wikipedia: “usually, courses of 2 adjacent strings are tuned in unison”. The pick strikes both strings of the pair; that is the sound the instrument is written for.
• The pairs are the tremolo mechanism. Wikipedia notes that mandolin notes decay quickly and that “the mandolin’s paired strings facilitate this technique: the plectrum (pick) strikes each of a pair of strings alternately, providing a more full and continuous sound than a single string would”. A mandolin with one string missing from a course does not tremolo properly, and that is audible rather than theoretical.
• The pair must agree, or the instrument fights itself. Two strings meant to be in unison but sitting a few cents apart beat against each other on every note. Tuning the pair precisely is not perfectionism — it is what makes the instrument sound like itself.
• Check the bridge is upright and in place. The bridge is a floating piece held against the soundboard by string pressure. If it has been knocked or the instrument has been restrung badly, the courses may sound in tune open but out of tune fretted.

Accuracy and limits

• A course is harder to read than a single string. The detector follows the combined signal from two strings, so a pair that disagrees produces a reading that wobbles between them. Get the course near the target with the display, then finish by ear against the beating between the two strings.
• The note dies quickly. Mandolin notes decay fast, so the steady part of the reading is short. Strike the course normally, let it ring, and watch the display settle instead of re-plucking.
• The E course is the bright, fragile one. The 1st course is tuned to E5 = 659.26 Hz and is the thinnest pair in the set. It reads easily but breaks most often; approach it slowly.
• Octave errors are easy to make and hard to hear. The mandolin’s G3 and the octave mandolin’s G2, or the D4 and D3, share a letter. If the preset and the instrument do not match, the display will look “right” while the target is an octave out. Check the card’s octave number, not just the letter.
• Fretted notes can disagree with open strings. If the open course is in tune but chords sound sour, check the bridge position and the nut slots rather than the tuning. A floating bridge that has drifted is the usual cause.
• Room noise and other instruments compete. In a session with guitars, fiddles or a banjo, the mandolin’s fast decay makes it the hardest instrument on the stage to read from a microphone. A clip-on tuner senses the headstock instead and is the better tool there.
• New strings settle for a day or two. Steel mandolin strings stretch at first. Tune, play for a few minutes, then check again before deciding the instrument has a problem.

Safety

• Bring strings up to pitch gradually. Eight steel strings at pitch carry real tension. Raise each course in small increments and stop at the target rather than shocking the string up from slack.
• Do not replace a whole course at once under tension. Change strings one at a time so the instrument keeps its tension and the bridge stays in place; taking all eight off together risks the bridge and the tailpiece moving.
• Never force a stiff machine head. If a tuner button will not turn, the string is usually binding in the nut or the tuner is dry. Ease it free rather than forcing it.
• Do not tune an octave too high. On the mandolin the 1st course target is E5 = 659.26 Hz and on the octave mandolin E4 = 329.63 Hz. An octave above either is roughly double the tension the string is built for.
• Watch the bridge and tailpiece while you tune. If the bridge leans or the tailpiece cover is loose, stop and set it right before continuing.
• Protect your hearing. A mandolin’s chop and tremolo are loud close to the ear; take breaks during long tuning and practice sessions.