You bet your life!

you (can) bet your (sweet) life

You can be absolutely certain that something will happen. (Sometimes used ironically. You bet your sweet life I'm going to that concert—I've been saving up for my ticket for months now! Oh, you can bet your life that Kevin will be late tonight—he's never on time! I lost my umbrella, so you can bet your life that it's going to rain soon.
See also: bet, life

You bet your (sweet) life!

 and You bet your boots!; You bet your life!; You bet your (sweet) bippy.
Inf. Fig. You can be absolutely certain of something! Mary: Will I need a coat today? Bill: You bet your sweet life! It's colder than an iceberg out there. Bill: Will you be at the game Saturday? Tom: You bet your boots!
See also: bet