How to Check a Used Guitar Before Buying

Buying & Setup

Ten minutes with a flashlight, a ruler and a tuner will tell you more than any listing photo.

What to bring

You do not need professional tools. A small kit is enough, and carrying it also tells the seller you are serious.

• A small flashlight, ideally a bright phone torch.
• A small mirror, to angle inside the soundhole.
• A millimetre ruler, preferably steel, for measuring the action.
• A clip-on tuner, or a tuner app on your phone.
• A soft cloth, so you can wipe dust off the areas you want to inspect.
• A phone, to photograph any damage you find so you can compare notes or negotiate.
• Your own picks, or your fingernails for classical, and a piece of music you know well enough to hear problems in.

Questions to ask the seller first

Before you travel, ask a few direct questions. Honest answers speed things up, and evasive ones tell you something too.

1. Is the guitar solid wood or laminate, and which parts are solid? The top matters most. Our article on solid and laminate tops explains the difference.
2. Has it ever been repaired? Cracks, neck resets, refrets and headstock repairs all affect value. Ask for details and photographs.
3. How was it stored? A guitar kept in a case in a stable room is a better bet than one left in a garage or near a heater.
4. Why are you selling it? The answer is sometimes useful and sometimes not, but it costs nothing to ask.
5. Are there original case, papers or receipts? These support the story and can add resale value.
6. Can I play it for ten minutes and look inside? A seller who says no is a warning sign.

Step 1: The overall look

Start with the guitar at arm's length, in good light, before you pick it up. Turn it slowly and look at the whole instrument.

• Does the top look flat, or is it domed around the bridge? A slight rise is normal. A big bulge with a dip in front of the bridge is not.
• Do the neck, body and headstock line up? Sight along the strings from the headstock to the bridge. The string should run straight toward the centre of the saddle.
• Does the finish look consistent, or are there patches that are glossier or darker than the rest? Mismatched areas often mean a repair.
• Is there any visible warping of the sides, or any gap where the sides meet the top or back?

Step 2: The top

The top carries the sound and takes the strings' pull, so it needs the closest look.

Cracks

Run a fingertip gently along the grain from the soundhole to the edge, and look at the surface with the light held low and at an angle, so the cracks show as fine lines. A short, tight, clean crack along the grain that does not move when you press on it is usually repairable, and the repair is often almost invisible. Warning signs include cracks that run across the grain, cracks that are open or uneven in height, cracks that continue under the bridge, and any crack that makes a buzz when you tap near it.

Belly and sunken areas

Hold a ruler across the top behind the bridge, and sight along it. A shallow belly is normal after years of string tension. A pronounced bulge, with a dip between the bridge and the soundhole, means the bracing is giving way. Our bracing guide explains what is happening underneath.

Bridge lifting

Look at the back edge of the bridge, the side farthest from the soundhole, and try to slide a thin piece of paper under it. On a steel-string guitar, where the bridge is glued on and pulled forward by high tension, any gap under the bridge is serious. On a classical guitar, the bridge is also glued, and a gap is a warning sign even though the tension is lower.

Wear and dents

Finger marks and pick scratches are cosmetic. Deep dents or marks near the edge may hide cracks beneath the finish, so inspect those areas closely.

Step 3: The finish

Fine cracks across a nitrocellulose finish, often called checking, are normal on old lacquered guitars and are cosmetic. Cracks that follow the grain of the wood are different: they are cracks in the wood itself. Learn to tell the two apart by running a fingernail across the line. A crack in the wood often catches a nail, and a finish check usually does not. Our finishes article explains the types and how each one ages.

Look for these as well:

• Cloudy or sticky patches. They suggest a poor repair or a reaction with a cleaner.
• Worn-through areas. Bare wood on the forearm or on the edge is normal use.
• Repainted or touched-up areas. A different sheen or an uneven edge can mean a hidden repair.

Step 4: The back and sides

Tap the sides and the back with a knuckle, and listen for buzzes or rattles. Check the seam down the centre of the back for opening, and look at the binding where the top, back and sides meet. Gaps in the binding, or places where it lifts, mean the glue is failing. Press gently on the back near the edges to check whether it is flexing. Look closely at the area around the end pin and the tail block, since a loose endpin or a crack near it can spread.

Step 5: The neck

The neck joint

Look at the heel, where the neck meets the body. A hairline gap or a crack in the finish around the joint suggests movement. Press down on the headstock gently while looking at the joint to see whether it shifts, though it should not.

Straightness

Sight along the neck from the headstock end toward the body, as you would sight along a rifle. It should be straight, with only a slight, even curve. A visible twist, or a hump near the body, means the neck has moved.

Relief and the truss rod

On a steel-string guitar, press the sixth string at the first and the last fret and check the gap at the middle, around the seventh or eighth fret. You are looking for a gap of roughly 0.2 to 0.3 millimetres, about the thickness of a business card, which is a small amount of forward relief. Too much gap means a bowed neck. No gap, or a string touching the frets, means a back bow. Check that the truss rod nut, at the headstock or inside the soundhole, is present and turns smoothly. Ask the seller to confirm that it works, and do not force it yourself. Our truss rod and action guide explains how it works.

Most classical guitars have no truss rod. Check the neck by eye and by playing it. A classical neck that has taken a bow cannot be adjusted from the headstock, so any visible curve is more serious than on a steel-string.

Step 6: The headstock

A crack or repair in the headstock is one of the most important things to look for. The area just behind the nut is a stress point, and a guitar that has been dropped or knocked often cracks there. Look for lines in the finish across the neck behind the nut, for uneven or thick finish in that area, and for any mismatch in colour or sheen. A clean, professional headstock repair can be strong and permanent, but it lowers the guitar's value. It is a point for negotiation, and it should be disclosed.

Check the tuners as well. They should turn smoothly, with no clicking, no slipping and no excessive play. Loose tuning machines can be tightened, and failed ones can be replaced, but it is useful to know in advance.

Step 7: The frets

Look along each fret for wear. Flat, shiny patches on the frets, particularly in the first five positions, mean the player has worn the metal down. Small grooves under the strings are a sign that the frets are due for work. Worn frets cause buzzing and dead notes, and a refret costs real money, so judge it with that in mind.

Run your fingertip along the edge of the fingerboard. Sharp fret ends sticking out from the sides are common on guitars that have dried out and shrunk, and they point to a dry history. They can be dressed, but they tell you how the guitar was stored. Also look for lifted frets, where a fret has come away from its slot, and for visible gaps beneath the fret wire.

Step 8: Action, nut and saddle

Measure the string height at the 12th fret, from the top of the fret to the bottom of the string, using your ruler. As a rough guide, which also appears in our action article, a steel-string guitar is comfortable at roughly 1.8 to 2.8 millimetres on the bass side and 1.5 to 2.3 on the treble side. A classical guitar sits higher, at roughly 3.2 to 4.7 millimetres on the bass side and 2.4 to 3.9 on the treble side. A reading well above these ranges means the guitar is hard to play, and the causes can range from a worn saddle to a collapsed neck angle.

Then check how the saddle sits. If the saddle is almost flush with the bridge on a guitar with high action, the neck angle may have shifted, which is a larger repair known as a neck reset. A bridge that has been raised or a saddle that has been shaved to nothing is a warning. Check the nut, where the strings sit at the headstock end. Slots that are too deep make the open strings buzz, and slots that are too high make the first frets hard to play.

Step 9: Inside the guitar

Hold the flashlight at the soundhole and angle the mirror inside to see the underside of the top. You are looking for several things.

• Loose or lifted braces. A gap along a brace edge, or a brace that moves when you press it with a pencil end, means the glue has failed.
• Cracks along the inside of the top. They are easier to see here than outside, especially near the bridge, soundhole and sides.
• Glue patches and repairs. Neat reinforcement is fine. Messy glue, drips or thick blobs suggest a poor repair.
• Label and serial number. They help confirm the model and year, and a missing or altered label is worth asking about.
• Loose debris. Pieces of wood rattling inside indicate a broken brace or bit of lining.

Step 10: Electronics, if it has them

If the guitar has a pickup and preamp, plug it in. Check each knob and switch for crackling, and listen for hum or dropouts. Open the battery compartment and inspect it for corrosion. An output jack that is loose or wobbling is a common failure and is usually easy to replace, but it is worth knowing before you pay.

Step 11: Play it

Check everything above, then play. Put the guitar through a proper test, not just a few chords.

1. Tune it fully. Note whether the strings hold their pitch over a few minutes, and whether the tuners turn smoothly.
2. Play every string at every fret. Listen for buzzes, dead notes and rattles. A buzz that appears in one area suggests a fret problem, and a buzz everywhere suggests low action or neck relief.
3. Check the intonation. Play the 12th-fret harmonic on each string, and then fret the same note. The two should be close. A big difference means the saddle or the strings may be at fault.
4. Play across the dynamic range. Play softly, then play hard. A guitar that cracks or rattles when you dig in has a loose part.
5. Listen to the balance. The bass and treble strings should be reasonably even. A guitar with a dull bass or weak trebles may have a top that is tired or a bridge that has moved.
6. Play it for longer than you think you need to. Ten minutes is a sensible minimum, because many problems only appear once you stop concentrating on the inspection.

Ask for a minute or two of silence at the end of the session, and listen to the guitar ring on. A guitar with good sustain, and a sound that you like, is the whole point. Everything else is repair cost.

Fixable or deal-breaker?

Problem	Usually	Notes
Worn strings, dirty fingerboard	Easy and cheap	Fresh strings and a clean cost little.
Loose tuners, crackling electronics	Easy to moderate	Parts are cheap, labour is small.
Worn saddle or nut	Easy to moderate	Replaceable, but may point to other problems.
Sharp fret ends	Moderate	Dressing the ends is routine. It also shows the guitar dried out.
Worn frets	Moderate to expensive	A dressing may be enough. A full refret costs more.
Small clean top crack	Moderate	Repairs well when properly done.
Loose brace	Moderate to expensive	Depends on how much of the guitar has to be opened.
Lifting bridge	Expensive	The bridge has to be removed and reglued, and the cause must be found.
Neck reset needed	Expensive	Common on old steel-string guitars. Often more than the guitar is worth.
Headstock break	Depends on the repair	A good repair is acceptable. A poor one is not.
Warped or twisted neck	Walk away	Hard or impossible to fix.
Severe belly with cracks	Walk away	The structure is failing.
Cracks across the grain	Walk away	These are hard to repair reliably.

Classical or steel-string: what changes

	Classical	Steel-string
Truss rod	Usually none, so check the neck by eye	Present. Check that it works
Main stress point	Top near the bridge and the bracing under it	Bridge lifting, neck angle and top belly
Bridge	Tie-block, strings knotted	Pins and a bridge plate. Check the pin holes for cracking
Typical wear	Nail wear on the top and rosette area, fret wear on the trebles	Pick wear, worn frets and corrosion on the hardware
Common repair	Cracks, loose braces and worn nuts	Neck reset, bridge reglue and refret
Strings to fit	Nylon, normally changed before testing	Steel. Do not over-tighten strings on an old top

Negotiating the price

Use what you found, politely and with evidence. A photo of a crack or a note of the measured action gives you a specific reason for a lower price, and it is harder to dismiss than a general complaint.

• Get repair estimates before you agree on a price, if the seller allows time. A guitar needing a refret and a neck reset is not a bargain at any price.
• Price in the cost of fresh strings, a setup and any repair you found.
• Compare the price to what the same model sells for in similar condition, not to the original list price.
• Be prepared to leave. A guitar you walk away from is a lesson. A guitar you regret buying is a bill.

Warning signs in a listing

• Photos that avoid the back of the headstock, the inside of the soundhole or the bridge area.
• A vague description with no mention of the wood, the age or the history.
• A price far below the going rate, with pressure to decide quickly.
• A seller who will not let you play, measure or look inside the guitar.
• A guitar described as vintage or rare without a serial number, label or papers.
• Ads that say "needs minor work" and do not say what the work is.

The short version

• Bring a flashlight, a mirror, a ruler and a tuner, and ask the seller about repairs and storage first.
• Check in this order: overall shape, top, finish, back and sides, neck, headstock, frets, action, inside, electronics, then play.
• Cracks along the grain, a belly behind the bridge, a lifting bridge and a twisted neck are the serious ones.
• Steel-string guitars have a truss rod, which you should test. Classical guitars generally do not, so a bowed neck is harder to put right.
• Worn strings, tuners, nuts and saddles are cheap. Neck resets, refrets and bracing repairs are not.
• Use what you find to negotiate, and be ready to walk away.