Guitar strings actually can be re-used, but unfortunately, they're not going to sound nearly as good. Not only is the string going to sound poor, but it's also going to be compromised structurally and therefore more likely to break after a few more weeks of use. \n\n\n\nWith that said, re-using, perhaps, one guitar string when it breaks is a great move to make if you don't want to go out there and purchase a brand new set just to get one. I actually do this all of the time, and I typically use the second method listed below when I want to re-use just one guitar string. \n\n\n\nHowever, most instrument shops actually sell individual strings nowadays, so it's not going to cost you much money to buy a single string. \n\n\n\nI think the real question is why would you want to re-use guitar strings? A pair of decent guitar strings made by Ernie Ball is typically around $7, and a premium set of guitar strings with the special anti-rust coating, for instance, Elixir brand, are around $12. \n\n\n\nIt's not going to cost you an arm and a leg to purchase a new set of guitar strings, and many of these brands give you the option of being able to purchase a five-pack of guitar strings for around $30-$40, which means you could be set for the entire year. \n\n\n\nThis is what I usually do, and I'm usually pretty happy with the purchase. Furthermore, each set of guitar strings is typically vacuum-sealed in a bag so they can last forever just sitting there. \n\n\n\nAssuming you've already opened them and they're out in the open, you can just place them in a sealed Ziplock bag to ensure their freshness. \n\n\n\nTruthfully, assuming you're playing the guitar every single day and you're gigging on a regular basis, a pair of solid guitar strings might last you around 2 months before they start to sound bad, although anti-rust strings from more premium brands tend to last much longer, and are truly worth the extra money, in my opinion. \n\n\n\nEventually, they lose that natural brightness and snap to them which sounds amazing. They begin to have a dull, lifeless sound, in addition to causing all kinds of weird sounds like buzzing and other strange ringing sounds due to the build-up of oils, dirt, grime, and other substances. \n\n\n\nIn my experience, old guitar strings sound more than just bad, they tend to buzz a lot more for whatever reason, and I find they have a "wobbly" sound to them, especially the high E and B string, particularly on the 12th to 17th fret. \n\n\n\nThis "wobbly" sound I'm referring to his a menace to your tone, and it makes playing the guitar very unpleasant. \n\n\n\nFurthermore, through the use of string conditioners and proper string maintenance, you could actually extend the life of them even much longer. I've already written about this in another post on the site, which I've linked at this link here, however, we'll briefly mention them right here. \n\n\n\nIf you want the maximum life out of your guitar strings, wash your hands with soap and water before each use; wipe off the strings with a micro-fibre cloth after you're done playing; use anti-rust strings from Elixir or another brand; use string conditioners, or purchase a humidifier which keeps your apartment\/house\/living space at the perfect range, which is typically around 40-60% humidity. \n\n\n\nWith that all said, let's say you're really eager to not spend the ~$10 every 2-3 months on a new set of strings, and you want to re-use them as much as possible. There are a few things that you can do. \n\n\n\nIt's worth noting before we jump into it that all of the strings actually have to be long enough to make it work. So if you intend on reusing guitar strings, always leave a bit of slack, that way you can reuse them.\n\n\n\nAdditionally, if you're using the lowest quality of guitar strings available, you might find that boiling them simply makes them more brittle and weak, and then they'll break. \n\n\n\nAlso, if you're repeating this process over and over again, what ends up happening is that there needs to be more tension to stretch the string so they're in tune. This might have the effect of putting undue tension and stress on your guitar's neck, effectively damaging the neck of the instrument. \n\n\n\nYou have to ask yourself if saving $10 is really worth the risk of potentially damaging your instrument. \n\n\n\n1) Boil the dirt\/grime\/oils off them. \n\n\n\nFor this, what you want to do is remove each guitar string individually and place them in a big pot\/pan filled with water. You can bring the guitar strings to a boil and cook them in there until the water looks nasty and noticeably dirty. \n\n\n\nOnce you've removed all of the grime off them, wipe them off with a clean micro-fiber cloth and then let them sit for a day or two.\n\n\n\nWhat this does is that it removes all of the materials that are making them sound bad, to begin with, however, the actual structural integrity of the string has been compromised due to repeated use, so they're never going to sound as good as they once did, but they'll sound a bit better, and you might get another week or two of playing them.\n\n\n\nSupposedly, what boiling the string does is that it allows the material to expand and contract, which releases all of the gunk they've collected over the hours you've put into the strings. \n\n\n\nSome people recommend that you wrap the guitar strings in aluminum foil and then put them in the oven, but I'd say it's a much better practice to just let them dry, but it's up to you how much time you're willing to wait. \n\n\n\nIf you do want to put them in the oven in a tinfoil wrap, just put them in there at low heat for around 15 minutes. \n\n\n\nRegardless, it's a good move to actually wipe them off after they've sat in the water with a dry cloth or towel of some sort. Remember, they are made out of steel, so you don't want them to sit there sopping wet, because then what'll happen is the inner core wire will rust and deteriorate in quality even more. \n\n\n\n2) Use a Super Fine Steel Wool To Wipe Off The Crime. \n\n\n\nGo on Amazon or to your local tool store and purchase superfine wool. Take off all of the guitar strings and use the super-fine wool to scrape off all of the guck off the strings. \n\n\n\nThis will work fine for scraping off all of the grime of the strings, however, as it was noted above, neither of these two methods will make the strings sound as good as they once did. \n\n\n\nIt's truly surprising how much gunk is collected on guitar strings, and you'll see this not only from the super-fine wool but also from the boiling process. There's a good chance the water will look quite murky once you're done. \n\n\n\nYouTube Video Tutorial \n\n\n\n\nhttps:\/\/www.youtube.com\/watch?v=ZXdcHyrjwdE&feature=youtu.be\n\n\n\n\nConclusion \n\n\n\nIn conclusion, I would honestly say that it's a much better practice to simply go out there and purchase a five-set of guitar strings, either from Elixir or from another brand that coats their product in anti-rust material, that way they last as long as possible. \n\n\n\nThe anti-rust coated guitar strings is really no joke. If you're willing to spend the $5 for each set of guitar strings, you might be able to make a five-set of Elixir strings last 3x as long.