Marathon mileage: how many miles a week do you need?
Marathon mileage for a first finish peaks at 25 to 35 miles a week; a 4:00 goal usually needs 35 to 50, and faster goals more. This page gives weekly mileage by goal, how a plan builds it and the minimum that still works. The generator sets your numbers from your current mileage and run days.
Weekly mileage for a marathon by goal
These are peak weeks, not starting weeks, and they are ranges rather than targets. A runner who finishes on 28 miles a week has not cut a corner; a runner who forces 50 on legs used to 20 has. The long run is the one fixed point, so the question is how many easy miles surround it.
| Goal | Peak weekly mileage | Run days | Plan |
|---|---|---|---|
| Finish, first marathon | 25 to 35 | 3 to 4 | Beginner marathon plan |
| Around 4:30 | 30 to 40 | 4 | 16-week plan |
| Around 4:00 | 35 to 50 | 4 to 5 | Intermediate plan, sub-4:00 |
| 3:30 and faster | 50 and up | 5 to 6 | 20-week plan with a goal time |
The pace that goes with each goal is on the marathon pace chart; the 4 hour page adds the splits.
Build your free marathon plan
Same engine as every plan on this site, but with your race date, your run days and your longest recent run. Prints to PDF, exports to your calendar. No signup.
How the generator sets your marathon mileage
The starting week is whichever is larger: the current weekly mileage you enter, or 4 miles for each run day you pick. The target peak week is 35 miles for a first marathon and 44 miles if you have run one before. The engine solves the weekly growth so the start reaches that peak by the last week before the taper, between 3 and 15 percent a week. Every fourth week drops to 82 percent of the week before as a cutback, except in the two weeks before the taper, and the long run is capped at 20 miles. The taper is the last three weeks.
Two examples from the engine. Enter 25 miles a week and a 10-mile long run, and the 16-week plan peaks at 35 miles in week 13, the last week before the taper. Enter 30 miles a week and a 12-mile long run, and the 18-week plan reaches 35 miles by week 3 and returns to it after every cutback until the taper: a higher start flattens the ramp instead of raising the peak. Leave the mileage blank and the 16-week plan starts from 16 miles on four run days and peaks at 35 in week 13. Enter your real number if you run more than that.
More run days raise the starting week without raising the long run. The same 16-week plan with nothing entered starts at 12 miles on three days and peaks at 33; on five days it starts at 20 and peaks at 35. The easy miles are spread across more days, and the long run stays the same length.
Minimum weekly mileage for a marathon
About 20 to 25 miles a week at the start of the plan, on three or four days, with a long run of 8 to 10 miles. Below that, the long run becomes too large a share of the week. An 18-mile run inside a 25-mile week means the other days are too short to prepare the legs for it, and that is where injuries start. A reasonable rule is that the long run stays under about half of the weekly total in the peak phase.
If you are under that today, spend four to eight weeks building the base first, then start a 20-week plan. Or use the couch to marathon plan, which starts lower and grows slower by design.
Weekly mileage vs marathon time
More miles make a faster marathon, up to the point where recovery fails, but the relationship is loose. Two runners on 40 miles a week can finish an hour apart. What the miles buy is the ability to hold your pace in the last 10K, which is where goal times are lost. The Riegel prediction the generator shows from a recent race assumes marathon-specific mileage. A 2:00 half predicts a 4:10 marathon only for a runner who did the long runs.
For a first marathon, chase the finish, not a mileage number. Run the plan, add miles only when the current week feels easy, and let the goal time wait for the second marathon. The sessions that fill those miles are described in marathon long runs and workouts, and the ramp-up schedule in how long to train for a marathon.
Frequently asked questions
How much weekly mileage do I need for a marathon?
25 to 35 miles a week at the peak to finish, 35 to 50 for a 4:00 goal, 50 and up for 3:30 and faster. Start from what you run now and let the plan set the weekly growth from there to the peak.
What should my weekly mileage be for a first marathon?
Start at 20 to 25 miles a week on three or four days and peak around 30 to 35 in the last peak week before the taper.
What is the minimum weekly mileage for a marathon?
About 20 miles a week at the start of the plan with an 8-mile long run. Less than that, build a base for a month or two first.
Does more weekly mileage mean a faster marathon?
Usually, within what you can recover from. Miles buy endurance for the last 10K; they do not replace the long run or a sensible pace on the day.
How fast should weekly mileage increase?
Between 3 and 15 percent a week, with a cutback every fourth week. The generator solves the rate from your starting volume and the target peak, so a higher start means a gentler ramp.