To quote my answer to another question:
The IPIP website provides measures of the Big 5. The following table from Furnham (1996) summarises some correlations across a few studies between the NEO Big 5 and the MBTI.
You can find a listing of some of the multi-construct measures including Big 5 measures on the ipip website.
References
- Furnham, A. (1996). The big five versus the big four: the relationship between the Myers-Briggs Type Indicator (MBTI) and NEO-PI five factor model of personality. Personality and Individual Differences, 21, 303-307.
