Internet applications have made our daily life fruitful. However, they also cause many security problems if these applications are leveraged by intruders. Thus, it is important to find and fix vulnerabilities timely to prevent application vulnerabilities from being exploited. Fuzz testing is a popular methodology that effectively finds vulnerabilities in application programs with seed input mutation. However, it is not a satisfied solution for the web browsers. In this work, we propose a solution, called scheduled DOM fuzzing (SDF), which integrates several related browser fuzzing tools and the fuzzing framework called BFF. To explore more crash possibilities, we revise the browser fuzzing architecture and schedule seed input selection and mutation dynamically. We also propose two probability computing methods in scheduling mechanism which tries to improve the performance by determining which combinations of seed and mutation would produce more crashes. Our experiments show that SDF is 2.27 time more efficient in terms of the number of crashes and vulnerabilities found at most. SDF also has the capacity for finding 23 exploitable crashes in Windows 7 within five days. The experimental results reveals that a good scheduling method for seed and mutations in browser fuzzing is able to find more exploitable crashes than fuzzers with the fixed seed input.