rear 12''. Was hoping for more of an 11'' but after ordering 11'' that I now have on front, They measured less than 10'' so I thought by buying 12'' I would get closer to 11'', wrong!! exactly what I ordered a full BIG/HUGE 12'' lol Well they'll come in handy on deep snow plowing I figure lol I'll trade them off next spring for 11'' mud lites! Believe it or not these Spartacus tires were only $64 and as heavy as they are @ 8 ply, free shipping lol and 3 day shipping! I'll keep em for snow tires.