Wild Mountain Runner Marathon Splits Calculator
Allows for an adjustment for your pace increasing or fading in later miles if you wish to plan that way

Enter Marathon Target Pace

minutes seconds per mile
with optional allowance for increasing or slowing to:
min sec per mile from miles

OR
Enter Marathon Target Time

Hours: Minutes:
Allow fade of  seconds per mile
per cent 		    from miles
Overall pace:  Pre-fade pace:  Post-fade pace: 
  1 mile:    2 miles:   3 miles:
  4 miles:   5 miles:   6 miles:
  7 miles:   8 miles:   9 miles:
10 miles: 11 miles: 12 miles:
13 miles: 14 miles: 15 miles:
16 miles: 17 miles: 18 miles:
19 miles: 20 miles: 21 miles:
22 miles: 23 miles: 24 miles:
25 miles: 26 miles:
Half-marathon split:  Calculated overall time: