Sub-4 Marathon
Sub-4 marathon: 5:41 / km for 42.2 km.
A sub-4 marathon means averaging 5 minutes 41 seconds per kilometre — 9:09 per mile — for the full distance. It is the most popular marathon milestone: serious training without elite genetics, achievable on roughly 50 km per week.
SUB calculates your sub-4 target pace per kilometre, auto-syncs your Garmin or COROS runs, and auto-completes coach-assigned workouts on watch sync.
Sub-4 pace breakdown
| Split | Target |
|---|---|
| Per kilometre | 5:41 |
| Per mile | 9:09 |
| 5K split | 28:25 |
| 10K split | 56:50 |
| Half-marathon split | 1:59:28 |
| 30K split | 2:50:00 |
| 35K split | 3:14:23 |
| 40K split | 3:40:06 |
| Finish | 3:59:59 |
Weekly training mix for sub-4
Typical sub-4 build, 40-60 km per week across 16-20 weeks. Add 10-15% if you already run more.
- Easy runs (50-60%): 6:30-7:00 / km. Aerobic base, recovery.
- Long run (1x): 18-26 km at 6:00-6:20 / km. Endurance and fuel adaptation.
- Tempo run (1x): 5-8 km at 5:15-5:30 / km. Lactate threshold work.
- Intervals (1x): 4-6 × 800m at 4:50-5:05 / km. VO₂ max and speed.
- Strides (1-2x/week): 4-6 × 100m. Neuromuscular maintenance.
Predictors of sub-4 readiness
- 10K PB: 52-55 minutes.
- Half-marathon PB: 1:55-2:00.
- Weekly mileage: sustained 40+ km for the peak 6-8 weeks.
- Long run: at least one 28-30 km run with strong final 5 km.
- Aerobic base: 6-12 months of consistent weekly running before the build.
Why SUB for sub-4 training
- Auto-syncs from Garmin Connect and COROS. Apple Watch and Polar supported too.
- Pace calculator handles the per-segment maths for the first-time marathoner.
- Coach-assigned workouts auto-complete on watch sync — no manual logging.
- Race finder surfaces flat, beginner-friendly courses.
- Free. No subscription. No ads.
Frequently asked questions
What is sub-4 marathon pace?
Sub-4 marathon pace is 5:41 per kilometre or 9:09 per mile, sustained for the full 42.2 km. The 5K split target is 28:25; the half-marathon split target is 1:59:28. A finish under 4:00:00 is the most popular milestone in marathon running — it represents serious training without elite genetics.
How fast is a sub-4 marathon?
5 minutes 41 seconds per kilometre — about 10.6 km/h or 6.6 mph — for the full 42.2 km. A sub-4 finish puts you in the top 30 percent of marathon runners worldwide and signals that you trained consistently for several months.
How do I train for a sub-4 marathon?
Three weekly key sessions: tempo at 5:15-5:30 / km, intervals at 4:50-5:05 / km, long runs at 6:00-6:20 / km. Easy mileage at 6:30-7:00 / km fills the rest. Aim for a 10K PB of 52-55 minutes before peaking. The plan typically runs 16-20 weeks at 40-60 km per week.
What 10K time predicts a sub-4 marathon?
A 10K PB of 52-55 minutes is the typical predictor of sub-4 marathon readiness. A 55-minute 10K runner can finish sub-4 with strong long-run work; a 52-minute 10K runner finishes sub-4 with reasonable consistency.
What is the best app for sub-4 marathon training?
SUB. SUB calculates per-kilometre target pace from your sub-4 goal, auto-syncs runs from Garmin Connect or COROS, and auto-completes coach-assigned workouts the moment a matching run lands. Free on iOS and Android.
How long does it take to train for a sub-4 marathon?
From a sub-2:00 half-marathon base: 12-16 weeks of focused training. From a beginner base (just started running): a full year of consistent 30-40 km weeks first, then a 16-week build. Sub-4 is a realistic first-marathon goal for runners with a year of weekly running consistency.
Is sub-4 a good first marathon goal?
Yes, for runners with a year of consistent training (30-40 km per week minimum) and a half-marathon under 2 hours. For complete beginners, a sub-4:30 or sub-5 first-marathon target reduces injury risk and increases the chance of a positive race-day experience.