How to Determine the Age of a Gibson J-45

By Anthony King
Legendary rock musician Eric Clapton performs using Gibson model acoustic guitars.

Gibson is a popular and collectible guitar brand. It remains one of the only guitar manufacturers to produce its instruments exclusively in the United States. Since 1989, all Gibson acoustic guitars have been made in Bozeman, Mont., and all Gibson electric guitars have been made in either Memphis, Tenn., or Nashville, Tenn. Knowing where the guitar was manufactured is straightforward, but knowing when it was made can be tricky, as Gibson's serial numbering system has changed numerous times through the years.

Check the back of the guitar headstock for an eight-digit serial number. If your guitar has an eight-digit serial number stamped on it, it was made after Gibson changed its numbering system in 1975. If there is no eight-digit serial number found, check the bottom of the guitar neck, which can be seen by looking inside of the guitar's sound hole. There will be a three- to six-digit number stamped in black, and possibly a two-digit number penciled in red.

If your guitar has an eight-digit serial number, it contains the year, date and the factory ranking number for the instrument. Make note of how the serial number will represent this information by referring to the sequence YDDDYRRR. In this sequence, "Y" indicates the year it was made, "D" indicates the day of the year, and the "R" represents the ranking number. For example, 80505210 means that the guitar was made on Feb. 19, 1985 and was the 210th instrument made that day. There are three exceptions to this rule. If the guitar was made in 1975, the eight-digit number will start with a "99." If the guitar was made in 1976, the guitar number will start with "00." Finally, if the guitar was made in 1977 the guitar's number will start with "06."

Unfortunately, there is no easy way to decipher serial codes of guitars made before 1975. Gibson used and reused numbers, changed numbering systems, and generally did not give much consideration to sequential numbering prior to its 1975 serial number system. Visit the Vintage Guitars Info Web site. This comprehensive guide will show all possible derivations of the old Gibson numbering system with information arranged by year. Be aware that the Gibson J-45 was not first produced until 1942.


In step 2, please note that the "D" in the code stands for the day of the year, not the day of the month. In the example, the "050" stands for the 50th day of the year, which is February 19th.

About the Author

Anthony King is a freelance writer and amateur filmmaker. His work has appeared in various online publications. He is currently working toward graduating with a B.A. in English-writing.