Mandy is the English diminutive of Amanda — from the Latin amandus (worthy of love, lovable). Played Rebecca Pearson on NBC's This Is Us (2016-2022) for six seasons — Emmy, Golden Globe, and SAG Award nominations. Mandy Patinkin is male (The Princess Bride, Homeland).
Mandy does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Mandy reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.