5 Reasons Your Guitar Won't Stay In Tune (and How to Fix Them)

Do you have problems keeping your guitar in tune? Before you think about swapping out your tuners, check out this video. StewMac guitar tech Gene Imbody shows you five of the most common tuning issues—and how to fix them.

Few things are more frustrating than a guitar that won’t stay in tune. You strum a chord, it sounds sweet — and by the next song, it’s already gone sour. The good news? There are clear reasons this happens, and once you understand them, you’ll know how to keep your guitar sounding its best.

Here are the five most common reasons your guitar slips out of tune — plus simple fixes to get you playing in tune longer.

1. Strings That Haven’t Settled In

New guitar strings stretch and equalize tension during the first session, so they’ll drift flat until they’re seated. Old, work-hardened strings lose elasticity and won’t hold pitch consistently.

Fix it:

When you put on new strings, stretch them gently as you tune up. Play for a few minutes, retune, and repeat. To make this process faster and easier, use our String Stretcha tool—it gets your guitar ready to play in tune instantly without the hand strain.
Replace strings regularly — especially if they feel gritty, sound dull, or are heavily dented from the frets.
Store a couple of spare sets in your case so you’re never caught off guard.

2. Nut Friction and Pinching

String binding at the nut is responsible for most tuning stability problems. If strings bind in the nut slots, they won’t glide smoothly when you bend, strum, or use the tuners. That’s a recipe for sharp notes and unstable tuning.

Fix it:

Make sure nut slots are cut to the right width for your gauge, with a smooth floor and the highest point at the fingerboard edge; slot should fall toward the headstock.
Use a touch of dry lube/graphite/PTFE (our Guitar Grease is a great choice) in each slot to reduce friction.
If tuning issues persist, consider having a tech dress or replace the nut.

We carry gauged nut slotting files, lubricants, and other guitar tools trusted by pro repair shops.

3. Tuning Machines & String Post Slippage

Good tuning machines rarely “slip”; most drift is from improper winds, nut friction or loose screws.

Fix it:

Snug bushing nuts and mounting screws (firm, not overtight).
If the tuners have button screws, make sure they are snug—too loose and the tuner may slip; too tight and it will be difficult to turn.
For non-locking posts, leave ~2–3 in (50–75 mm) of slack, make 2–3 wraps (bass) / 3–5 (treble), and spiral wraps downward. Consider a simple “capstan-lock” (first wrap crosses over itself) for extra security.
Locking tuners: pull string taut, ~½–1 wrap max.
Upgrade only if parts are worn or rough.

4. Tremolo and Bridge Issues

Floating systems go out of tune if spring tension, knife-edges, or friction points aren’t right. Small changes here affect tuning stability (not intonation).

Fix it:

Depress and release the tremolo arm aggressively, then check with a tuner to ensure it returns to the same pitch. If it doesn’t, inspect the springs and pivot contact points for issues. Consider adding a Hipshot Tremsetter for improved return precision.Balance springs so the bridge sits parallel to the top at rest.
De-burr/polish saddles and check string trees; a micro-touch of dry lube helps. The Graph Tech String Saver Saddles are a great way to avoid these problems in the first place.
Not using the trem? Deck or block it for maximum stability.

5. Environment and Playing Habits

Temperature, humidity, and even how hard you play can impact tuning. Wood expands and contracts with climate changes, and heavy-handed strumming or bending stretches strings past their comfort zone.

Fix it:

Store guitars in a case with a humidifier if you live in a dry area. Aim for ~45-50% relative humidity.
Give your guitar a few minutes to acclimate when moving between hot and cold environments.
Play with a lighter attack and check setup if you notice you’re constantly pulling things sharp.

Quick Troubleshooting Checklist

Are your strings fresh and stretched in?
Do the nut slots fit and glide smoothly?
Are your tuners secure and stable?
Is your bridge properly set up?
Is your environment guitar-friendly?

If you answered “no” to any of these, that’s likely the culprit.

Stay in Tune, Stay Inspired

A guitar that won’t stay in tune is more than an annoyance — it’s a barrier to enjoying your playing. The good news is that with the right setup, fresh strings, and a few simple tweaks, you can solve most tuning issues quickly.

At StewMac, we’ve been building and repairing guitars for decades, and we’ve seen every tuning problem under the sun. That’s why we stock the luthier tools, parts, and expert resources you need to keep your guitar playing (and sounding) its best.

Check out our array of guitar setup tools and maintenance supplies — and keep your instrument rock solid in tune.

Video Transcription

[on-screen text reads: Gene - StewMac Tech]

Gene Imbody: Getting your guitar in tune and more importantly, keeping your guitar in tune, is something all guitars struggle with at some point. But before you go out and spend a bunch of money on fancy new tuners, check out this video because I'm going to give you five of the most common reasons your guitar might not be holding tune. And spoiler alert, none of them have to do with buying new tuners. And if you stick around until the end, I'm going to throw in a bonus tip that not only will help you with tuning, but it's going to make you a better player too.

Problem #1: The strings

The first thing I check when customers tell me they're having trouble keeping their guitar in tune is how they've wound the string to the post. This is critical. If you haven't installed your strings correctly, it's guaranteed you're not going to stay in tune. In most cases, you don't have to get locking tuners to make sure your strings don't slip on the post, and god forbid, don't tie any knots. You don't need to do any fancy tricks. A tuner post is engineered to hold your strings in place with a simple wind. There's several ways to do it well, but the simplest always works best for me. Insert the string through the post hole and give yourself a few inches of slack for the winds. Use a string winder to give yourself about half a wrap. Not nearly enough by any measure, but check this out. Even with just half a wrap, I can pretty much pick this guitar up by this thin string. As long as I keep tension on it, it's locked into place.

All you need from this point on is several neat wraps, three to four on the wound strings and four to six on the unwound, one after another, heading downward toward the peghead. If you want some more help with changing your strings, check out this video. We'll give you some added detail and even more helpful tips to help you along the way.

Another common reason strings won't hold tune is because they need to be stretched out properly. All new strings go through a stage where the metal stretches a little bit and the small amount of slack left in the winds needs to be pulled out. If you aren't in a hurry, you can just let that happen naturally, usually in a matter of hours with some tunings and retunings. But if you want them to stay in tune fast, you can use your hand or this cool little string stretching device we sell to help them out [on-screen text reads: The String Stretcha]. Give them all a gentle pull up and down the length of the string, retune and repeat. You'll know you're there when you stretch, check on your tuner, and you're still in tune or pretty close to it.

Problem #2: The tuners

The tuners and the bridge are your two anchor points of the string. They need to be totally stable or you're not going to stay in tune. So first off, make sure your mounting hardware is tight. Check your knob screws if you have them, the mounting screws, if you have threaded bushing tuners, make sure they're snug too. I like the spanner wrench for the bushings. It fits any size and it allows you to tighten them while the strings are in place.

Now in my experience, the tuners get way too much of the blame for tuning issues. Like I said, if you've installed the strings properly and all your hardware is tight, you should be good to go, no matter what quality tuners you have. A more likely issue that you may be having with your tuners is that you're not tuning correctly. You need to be tuning up to pitch, not down to pitch, like this.

Start a little flat and then tighten the tension so you are coming up to the note. If you've gone past your target, tune back down and then come up again. The reason you do this is because there may still be some slack in the gear or in the string, and that can cause you to continue to drift flat a little bit. This isn't a big deal with modern high quality tuners. The best tuners can go both directions, but it's a good habit to get into. And if you have vintage tuners, this is critical in my opinion.

Problem #3: The bridge

As I mentioned, you have two anchor points to a string that need to be completely stable. The bridge, or your tailpiece or vibrato, whatever you have, wherever the ball ends seat is that second anchor. In the case of a fixed bridge guitar, like a Fender Telecaster or a Gibson with a tune-o-matic, that means nothing can move. Screws need to be tight, bushings need to be seated well and stationary. I like to check pretty much anytime I change the strings, check out this Les Paul. With the strings off, I can make sure there's no looseness to the fit of the posts or the bushings. If anything is leaning or wobbling, that's a major problem. Holes can be plugged and redrilled, but that can be tricky. So you may want to consult a repair shop for that type of work.

Same for a Telecaster or a Hardtail Strat. It's always a good idea to check your mounting screws. If these screws won't tighten properly, the holes can be plugged and redrilled, like I mentioned earlier, fortunately these aren't super common issues. If you have a guitar with an archtop style tailpiece or a Bigsby vibrato, check your screws there periodically as well. And if you have a bolt-on neck, you guessed it, check those screws.

You want to be aware of the condition of any part of the guitar that directly supports the pull of the strings. Now it gets a little more complex when dealing with the Tremolo, since that's a moving system. The key there is to make sure the Trem claw screws are solid. They need to grab well and not feel loose in their holes. Same with the mounting studs, like the posts on a Gibson, they shouldn't lean wobble or pull out. Past that, the Trem should move smoothly and it should return to the same position when you release it. We'll get into the details of setting up a guitar with a Tremolo in another video. Just keep in mind that if you have a Trem, that's certainly going to affect your tune.

Problem #4: Intonation

Intonation refers to how accurately your guitar plays in tune as you move up the neck, you must be properly intonated for your guitar to play in tune to its full potential. You do this by making small adjustments to the length of your string through your saddles. You move your saddle back to make your string more flat, move your saddle forward to make the string more sharp.

Here's how most people check to make sure their guitar is properly intonated. Play your open note. Check the fretted 12th note. These two notes should match. If they don't, make small adjustments to the saddle, retune and check again. A lot of people think this is something only a tech can do, but if you're patient and you have a good tuner, this is absolutely something you can do yourself. Check out this link right here to watch our video dedicated to intonation and you'll have it down [on-screen text reads: How to Intonate Your Guitar].

One thing I want to point out, and this is really important, you're never going to be perfectly intonated in every spot on the board. For anyone who's ever intonated a guitar, you may have been in this situation. You're perfectly in tune at the 12th fret, but you have some other spots on the board with sour notes, particularly in the first position on your open chords, sometimes referred to as cowboy chords. You may have assumed there was something else wrong with your guitar, but like I said, the guitar is an imperfect instrument. There are always going to be some notes along the way that are going to be a little bit out of tune.

The idea behind intonation is to spread the error out so that not any one spot is any more out of tune than any other. What I tend to find is that sharp notes are very offensive to the ear. Flat notes not quite as much. So if I do find some overly sharp notes in the first position, I'll move my saddles even further back to help correct that. That usually means being a little bit flat at the 12th fret. But that doesn't bother me nearly as much as the sharp notes in the first position. The point I want to convey here is to not be so caught up with the fact that you need to be perfect at the 12th fret, you can set your intonation to correct the problems wherever they bother you the most.

Problem #5: The nut

Believe it or not, most tuning issues come down to the nut. Do not go spend a bunch of money on fancy new tuners until you make sure you have a properly functioning nut. First off, the slots in the nut have to be at the right height. The further you have to stretch the string to touch the fret, the sharper the note is going to be and the harder it will be to intonate the guitar.

So how do you know if your nut is at the right height? Well we have a lot of tools that can help you with this, but let me see if I can simplify it for you. Think of the nut as a fret that's always fretted, like a zero fret. Much in the same way that the first fret doesn't need to be any higher than the second fret when your fret notes there, and the second fret doesn't need to be any higher than the third fret when your fret notes there. Theoretically, the height of the strings over the first fret shouldn't need to be any higher than the height of the strings over the second fret when you're fretted at the first.

What? Now that's a mouthful. So let's take a look at it. Put a capo at the first fret and look at the height of the strings over the second on this guitar. You can measure this height with Feeler Gauges or even a guitar string bent at a right angle. Now I can tell you from experience, open strings tend to move more. People tend to strike open notes harder. So take that measurement and double it [Gene writes .010" x 2 = .020" on a notepad]. That's the height you want to see from the top of the first fret to the bottom of the string. It's a little extra insurance to make sure you're not going to buzz.

I can see on this guitar that the height of my string over the first fret is more than double what it was on the second fret. I'm going to move the string and use a nut file to lower it a little bit. Then we replace the string and check it again. Go slowly and repeat that until you are where you need to be. Now be careful, if you lower the slot too much, you could end up buzzing and then you might have to replace the whole nut.

Ah!

Now let's talk about the biggest culprit I see for tuning issues. Have you ever tried tuning your string and noticed that nothing's happening right at first and then suddenly you're sharp or flat of where you were trying to be? Here's what's happening. The nut slot, usually at the back where the strings leave the tuners and enter the nut slot at an angle, is pinching the strings and not allowing them to move freely. So how do you fix this? You need to reshape the slots so they don't impede the movement of the strings. The first place to concentrate is the back of the slot where the strings enter. We're going for something that looks like a funnel that has been cut in half. Gauged nut files are best for this, but if you don't have those, you can use folded sandpaper, sanding cord, or a very small half round or V-shaped needle file.

I'm flaring out the back edge so that the entry angle of the string doesn't catch on the corners. I like to hit both sides. Roll the file as you relieve the edges and add some angle to the bottom of the slot to create a bit of a ramp towards the front edge. If your nut action is good, be sure you're staying off the very front of the slot, or you will also lower the height of the strings. After you've done your shaping, go back with high grit sandpaper to smooth everything out, I fold up 600 and a thousand grit to get something close to the diameter of the string I'm working on. It's not a bad idea when you're done shaping to use a string of the same gauge to floss the slot. What I'm checking for here is to make sure that the string wants to move through without grabbing.

So I started with the D and the G because those are the two worst culprits on a three left, three right peghead, because of that angle coming into the back of the slot. But I'll hit all six strings the same. I might exaggerate the funnel a little bit on those, but each one of them will get the same treatment. The last thing to consider is how deeply the strings are buried in the slots. If there's too much material above the string, this can hang them up as well. I like to shoot for half the depth of the wound strings and to just feel the tops of the unwound strings. These strings are clearly sitting way too deep into the nut, so let's fix that. You can do this right on the guitar, but be sure to tape off and protect your finish. If your nut comes out easily, go ahead and remove it and do this work in a vice.

All I do is use our nut shaping files or a radius block to remove the excess from the top and expose some strings. Don't go too far, leave yourself a little extra to sand out the scratches and polish when you're done. Now the one thing I'll say is if you have an inexpensive guitar with a plastic nut, you might just consider having it replaced. I like bone the best, but really plastic is too soft to be doing this kind of work too.

Bonus Tip!

So I said I was going to give you a bonus tip to help with your tuning and make you a better player, so here it is. Improving the ability of your guitar to stay in tune is a matter of controlling variables. And the biggest variable is you, the player. The better your technique and the lighter your touch, the more your guitar will play in tune. If you have a death grip on your fretting hand, learn to relax. If you have a wild out of control picking hand, practice precision. And finally, train yourself to tune by ear. Treat your ear like a muscle and exercise it. Practice using a tuning fork and identifying pitch. Electronic tuners definitely have their place, but make sure it's a tool, not a crutch. If you're able to trust your ear, you'll be a better repair person and a better player.