What my name kanji is?

Hi I am a Peruvian-Japanese-American nikkei
My Obashan always told me that my name Yukihiro means (big and powerful heart)
I never know my kanji or how to write my name.
Could someone please help me?

There are many ways to write Yukihiro in kanji: http://jisho.org/search/Yukihiro%20%23names

Kanji is a combination of meaning. Many caracters can have to same pronunciation but different meaning.

This is only known by your parents.

When people tell there name in Japan often they say the kanji meaning.

If you are a Japanese citizen, you have a Koseki and your name is written in kanji there. Otherwise, your name is not written in kanji. You can use whatever kanji you want in informal settings, just like other non-Japanese sometimes write their name in kanji for fun.

Hello. From Japan.

Maybe, I think Yukihiro is "幸大" what written by Kanji.
In Japanese, 幸(Yuki) means Happy heart and Happiness. 大(hiro) means Big and Worldwide and more.

Your Name is so great.