How to discover how old is an johnnie walker scotch?I have an old bottle but the year is nowhere written

Only the Blue Label brand has a serial number on the bottle. No others are marked or dated coded.

Rest assured, Red label is aged at least 8 years, Black 12 years, Green 15 years, and Gold 15-18 years, before bottling.

If you have any unopened JW bottle your concerned are too old, I will be glad to take them.

I finally discover everything I wanted to know,I even found a buyer:)
Thanks anyway

I believe the blue label version has some 60 year old Scotch in it! JW does not have an age statement because it is blended Scotch. Usually only single malts will have an age.

Bonus answer: the green label version is a "vatted" blend, meaning it contains only malt whisky; all other JW blends contain some grain whisky.

PS - the correct spelling is Johnnie Walker.