What this result means
A marathon is 42.195 kilometres, or 26.219 miles. Enter a target time to see the average pace required, speed, and even splits. The calculator does not predict a marathon from a half — it only splits the marathon you asked for.
Boston, London, and most majors are certified at 42.195 km. “Sub-3” means 2:59:59, which is a faster pace than a 3:00:00 even-split table. Set the clock to the time you actually want, including any buffer.
A 4:00:00 marathon requires about 5:41/km or 9:09/mile. Even splits put half marathon near 2:00:00 and 20 miles near 3:02:55. A 3:00:00 marathon is about 4:16/km or 6:52/mile — the same pace as a 1:30 half, held more than twice as long.
A 3:30:00 marathon is about 4:59/km or 8:01/mile, close to a 1:45 half on paper. Fueling, muscle damage, and weather make those two efforts different. This page only reports the average.
Calculation method
Pace is finish time divided by 42.195 km. Splits divide that time evenly across kilometres or miles. Displayed times round to the nearest second.
This is exact arithmetic. It is not a fade model, a heat adjustment, or a “positive split” planner. If you plan to run the second half slower, set a faster first-half target yourself.
Marathon even splits are a goal many people miss. Caffeine, gels, and a conservative first 10K are outside this tool. Use the race time predictor if you only have a shorter race and want a planning estimate.
Frequently asked questions
What pace is a 4-hour marathon?
About 5:41 per kilometre, or 9:09 per mile. Even splits put the half at 2:00:00.
What pace is a 3-hour marathon?
About 4:16 per kilometre, or 6:52 per mile. Enter 3:00:00 for the full split table.
How long is a marathon?
42.195 kilometres (26.219 miles). This tool uses that distance, not 42 km or 26 miles.
Should I run even splits in a marathon?
Even splits are a common target. Many runners go slightly conservative early. The table is a reference, not a requirement.