We guarantee fresh product when we ship. We mark expiration dates in two formats. One is as simple as MM/DD/YY, the other is a 5 digit code that requires some interpretation. Check out our BLOG for more details.You can find the 5-digit code on the cap or the bottle/bag of our product. It includes one letter and four digits of numbers. (i.e. J2345) To decode, divide the code into three sections. The letter indicates the year. i.e. I = 2016 J = 2017 K = 2018. The first two numbers subtracting 20 indicate the month. i.e. 23 – 20 = 03 (March) The last two numbers subtracting 20 indicate the day. i.e. 45 - 20 = 25 (25th).