I have read articles stating that Albert Einstein had an average brain volume but couldn't find a specific measurement. I'm curious because the articles are all so ambiguous. He could have been on the upper or lower side of average.
I was interested in the same question a while ago. Unfortunately, Witelson et al (1999) reported here (http://penthai.sc.mahidol.ac.th/html/articles/newsletter/paper3.pdf) that volume measurements haven't been taken at the time. Weight data is available, but weight and volume aren't correlated perfectly.
Witelson, S. F., Kigar, D. L., & Harvey, T. (1999). The exceptional brain of Albert Einstein. The Lancet, 353(9170), 2149-2153.