How long will it take 1.5 mg of klonopin to get out of my blood?

Four days. The answer is four 1/2 lives... taken from a pharmacology website: “After 4 half-lives the amount of drug (6.25%) is considered to be negligible regarding its therapeutic effects”.

Given that Klonopin doesn’t have major active metabolites, and the ‘average ‘ one-day 1/2 life of Klonopin (though some texts cite 20-80 hours, there’s no way it’s anywhere near 80 hours in real-world practice .
4-5 days. Klonopin half life, the time taken to cleanse half of it from your body, is about 20-50 hours, so roughly double that time or more will be the time needed to get rid of it all, good luck .