Negative Split Planner

Plan your first and second half targets. Running a controlled first half typically leads to a stronger finish.

GOAL MARATHON TIME

UNIT

SPLIT STRATEGY

50/50 (Even split)51/49 (Slight negative)52/48 (Moderate negative)53/47 (Aggressive negative)

First Half

1:47:06

Pace: 8:10/mi

51% of total

Second Half (Stronger)

1:42:54

Pace: 7:51/mi

49% of total

Total: 3:30:00  |  Pace difference: 0:19/mi faster in second half

Studies of Boston Marathon finishers show that runners who go out 1-3% slower in the first half are significantly more likely to achieve their goal time than those who run even or positive splits.