Japanese Word for Confidence
We use Japanese Kanji word "信任(しんにん-shinnin)" for translating English word "Confidence" into Japanese. I showed large Japanese kanji image of this Japanese word in left side of this page.
And we have a few some other Japanese words also used for "Confidence" such as "信頼(しんらい-shinrai)[also means "Trust"]", "信用(しんよう-shinyou)[also means "Credit"]" and "確信(かくしん-kakushin)[also means "Conviction"]" etc.
These Japanese words are often used same way but in some case they are used differently depend on the situations especially the word "確信".
And for the word "Self-Confidence", we use kanji word "自信(じしん-jishin)" in Japan.
Please refer this post too.