Where is the housing market most on the upswing for buyers and sellers this spring? Realtor.com® recently analyzed 300 of the largest housing markets to come up with a list of the nation's 20 hottest real estate markets. The rankings are based on the number of views per listing on realtor.com® (which helps to gauge buyer demand) as well as the median age of inventory (to analyze the supply). 

Realtor.com® ranked the following 20 housing markets as the hottest in May: 

1. Denver-Aurora-Lakewood, Colo.
2. San Francisco-Oakland-Hayward, Calif.
3. San Jose-Sunnyvale-Santa Clara, Calif. 
4. Dallas-Fort Worth-Arlington, Texas
5. Vallejo-Fairfield, Calif.
6. Boston-Cambridge-Newton, Mass.-N.H.
7. Santa Cruz-Watsonville, Calif.
8. Santa Rosa, Calif.
9. Ann Arbor, Mich.
10. Detroit-Warren-Dearborn, Mich.
11. San Diego-Carlsbad, Calif.
12. Sacramento-Roseville-Arden-Arcade, Calif.
13. Boulder, Colo.
14. Fargo, N.D.-MN
15. Los Angeles-Long Beach-Anaheim, Calif.
16. Austin-Round Rock, Texas
17. Oxnard-Thousand Oaks-Ventura, Calif.
18. Manchester-Nashua, N.H.
19. Columbus, Ohio
20. Stockton-Lodi, Calif.