I am learning Japanese on my own. I finished grammer topics, and now I am studying on Kanji. I have already memorized about 150 kanjis yet.
During my study I realized that some of Japanese kanji are same with Chinese kanji, also in the meaning.

I want to ask that if Japanese and Chinese kanji are completely same, or Chinese kanji set encapsulates Japanese kanji set (I heard that Chinese language has no syllable alphabet like hiragana and katakana, if so Chinese language should have more kanji by simple logic).

Can you explain it?