The age of a Gibson guitar, along with the physical condition and relative rarity, are the major factors in determining its value. While physical condition can be assessed with a careful inspection, rarity and date of manufacture are not always easy to determine. But the serial number on a Gibson can tell you when the guitar was made. With that information, you can determine its rarity and, ultimately, its worth.
Locate the serial number on your Gibson. For acoustic instruments, the serial number is typically located inside the sound hole at the neck joint or on a piece of paper glued inside the guitar and visible through the sound hole. On electric guitars, the serial number is generally printed on the back of the headstock.
Decipher your serial number if it's eight digits. Since 1977, Gibson has used the following method: The first and fifth numbers indicate the last two digits of the year the instrument was produced, the second through fourth digits tell the day of the year it was produced and the last three digits indicate the production rank. For example, the serial number 81449243 means the guitar was the 243rd instrument made on the 144th day of 1989.
Use the Blue Book of Electric Guitars, available for free at Gibson's website, to date your instrument if it has a different type of serial number. Over the years, Gibson has gone through several different serial-number changes, sometimes resulting in multiple guitars with the same number. The book, which lists all the company's historical serial number schemes, is an invaluable resource when dating vintage Gibson guitars.
If you're still having trouble accurately dating your Gibson, take pictures of the guitar, including the serial number, and upload them to the customer service section on the company's website. In most cases, they'll help you date your instrument.