.NET FAQ - Measure Code Execution Time

A common method used to measure the amount of time a peice of code takes to execute is to take multiple time snapshots using DateTime.Now, and then comparing those snapshots. While this certainly works, it’s not the most accurate way to measure. A better way is to use the Stopwatch class in the System.Diagnostics namespace.

Stopwatch Example

var sw = Stopwatch.StartNew();
//your code
sw.Stop();

Debug.WriteLine("Elapsed time: {0}", sw.Elapsed.TotalMilliseconds);