How do I calculate my percentage of body weight lost?

I would like to calculate my total percentage lost like on the biggest loser. How do I do that?How do I calculate my percentage of body weight lost?
put the percentage of the weight you lost over ( /) your previous body weight and then multiply by 100How do I calculate my percentage of body weight lost?
To get your body fat % you need what you had at the beginning I hope you had that. Then get a caliper and take measurements at your belly, chest, hits, and lower back.

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