They should be good for minimum 5 years in a cool dry dark place, in an airtight jar.
After 5 years, germ rates start to decline by about 10% a year.

That is how fem seeds are made. Pick only excellent representatives to work with, and don't ever use a female that throws nanners under normal grow conditions. Use one who has to be stressed pretty bad to show male parts.

Clones ARE the bombdiggity. Learn to take them and your life gets super easier.