These mock exams are all official workbooks of the Japanese Language Proficiency Test. With the exception of the Listening section which I’ve provided the Youtube links for, these are all free pdfs:
JLPT Mock Exams:
N5:
Vocabulary
Grammar
Listening (Youtube)
Answers
N4:
Vocabulary
Reading
Grammar
Listening (Youtube)
Answers
N3:
Vocabulary
Grammar
Reading
Listening (Youtube)
Answer Sheet
N2:
VocabularyGrammar
Listening (Youtube)
ReadingAnswer Sheet
N1:
Vocabulary
Grammar
Reading
Listening (Youtube)
Answer Sheet