Big Five is a dimensional model rooted in modern psychometrics; Jungian Type is a categorical model with four bipolar preferences. They answer different kinds of questions about who you are.
Measure your personality across five major dimensions: Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism. Based on the IPIP public domain item pool.
Discover your cognitive preferences across four dimensions: Extraversion/Introversion, Sensing/Intuition, Thinking/Feeling, and Judging/Perceiving. Results are shown as your four spelled-out preferences.
Taking both gives you two angles on the same person — you. Many users find the discrepancies more interesting than the agreements.