The number of steps in a mile will vary, depending on the length of your stride. The pedometer I had (before it broke) allowed me to put in the length of my steps (mine was about 18") and it calculated the number of steps I needed to make a mile. Therefore, for me, it took about 3700 steps to make a mile.
Here's a site that will make the calculation for you, if your pedometer doesn't have that function. Once you know your average steps/mile, you won't have to calculate it every time.
There are other sites that will do the same thing.
To calculate it yourself, figure out how long your stride is then divide 5280 (feet per mile) by your stride length. Lay a tape measure on the ground and take a few normal steps beside it to get your average stride length. Be aware that not all your steps will be exactly the same.
In my case, my stride length is approximately 18", which is 1 foot, 6 inches or 1.5 feet. 5280/1.5 is 3520, so the 3700 steps I noted above is incorrect.
sorry about that. invest in a very inexpensive pedometer.. it will help with counting ur steps