Marathon Pace Calculator
Pace per Kilometer
—
Pace per Mile
—
Speed (km/h)
—
5K Split
—
How to Pace Your Marathon
Pacing is the single most important strategy for marathons. To calculate pace: divide total time (seconds) by distance (km or miles). A 4-hour marathon requires 5:41/km or 9:09/mile. Even pacing or slight negative splits (faster second half) is the most efficient strategy.
This calculator works for marathon (42.195 km), half marathon (21.0975 km), 10K, and 5K races. It shows your required pace per km and per mile, along with 5K split times to check during the race.
Common mistakes: starting too fast (burning glycogen early), not accounting for hills, and ignoring weather conditions. In hot weather, add 1-2% per degree Celsius above 15°C. For hilly courses, focus on effort rather than exact pace on inclines.
Frequently Asked Questions
What pace do I need for a 4-hour marathon?
5:41 per km or 9:09 per mile. This is a common target for recreational runners.
Should I run negative splits?
Ideally yes — running the second half slightly faster than the first. This requires discipline to start conservatively. Even splits are also excellent.
How does elevation affect pace?
Uphill slows pace roughly 12-15 seconds per mile per 1% grade. Downhill gains back about 8 seconds per mile per 1% grade. Focus on consistent effort, not pace, on hills.
What is a good first marathon time?
Average first marathon time is about 4:30-5:00. Under 4 hours is a common goal. Sub-3 is competitive for recreational runners.