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Hit your goal time
A precise pace target, broken into 5 km splits, beats running by feel. The watch keeps you honest.
🏃 Free Marathon Pace Calculator
Calculate your
Marathon Pace
and splits — instantly
Enter a finish time, get the pace and every split. Or enter a pace, get the projected finish. Works for marathon, half marathon, 10K, 5K and custom distances.
No subscription · No credit card · Start instantly · Last updated May 2026
Marathon
Half Marathon
10K
5K
Splits
min/km · km/h
Negative Split
Calculator
Marathon Pace Calculator
Toggle between Time → Pace and Pace → Time. Splits update live.
Enter finish time → calculate pace
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:
Hours
Minutes
Seconds
📍 Split times
| Distance | Split time | Pace |
|---|
Why pace matters
Pacing decides
the race
Most marathons are lost in the first 10 km — runners go out too hot and pay for it after kilometre 30. A clear pace plan fixes this.
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Avoid the wall
Going out 10–15 sec/km too fast costs you minutes after kilometre 30. The calculator shows the limit.
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5 km splits, live
The split table updates as you change inputs. Bookmark the line you'll hit at every aid station.
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min/km ↔ km/h
Both metrics shown side by side. Convert between them without doing the maths in your head.
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Bidirectional
Either start from your goal time and learn the pace, or start from a pace and project the finish.
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All distances
Marathon, half, 10K, 5K — plus a custom distance field for any interim race or training tempo run.
How to pace
Three rules for a strong race
A solid pacing strategy is the difference between a finisher and a personal best.
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1
Start 5–10 sec/km slower than goal pace
The first 5 km should feel almost too easy. Runners around you will pull away — let them. Glycogen burnt early is glycogen you don't have at km 35.
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2
Lock onto goal pace from km 5 to km 30
This is your race. Run the splits the calculator gave you. Don't surge for hills — keep effort constant; pace will rise on descents and that's fine.
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3
Earn the negative split in the last 12 km
If you've paced patiently, the last 12 km feel hard but doable. From km 30, allow pace to drop 5–10 sec/km. That's the negative split — and the way world records get set.
Pace table
Marathon pace — all finish times
Quick reference for the most common goal times, with required pace, speed and half marathon split.
| Finish time | Pace (min/km) | Speed (km/h) | Half marathon split |
|---|---|---|---|
| Sub 3h 2:59:59 | 4:15 | 14.1 | 1:29:30 |
| 3:00:00 | 4:16 | 14.1 | 1:30:00 |
| 3:15:00 | 4:37 | 13.0 | 1:37:30 |
| 3:30:00 | 4:59 | 12.1 | 1:45:00 |
| Sub 4h 3:45:00 | 5:19 | 11.3 | 1:52:30 |
| 3:59:59 | 5:41 | 10.6 | 2:00:00 |
| 4:00:00 | 5:41 | 10.5 | 2:00:00 |
| 4:15:00 | 6:03 | 9.9 | 2:07:30 |
| 4:30:00 | 6:24 | 9.4 | 2:15:00 |
| 4:45:00 | 6:45 | 8.9 | 2:22:30 |
| Sub 5h 4:59:59 | 7:06 | 8.4 | 2:30:00 |
| 5:00:00 | 7:06 | 8.4 | 2:30:00 |
| 5:30:00 | 7:49 | 7.7 | 2:45:00 |
| 6:00:00 | 8:31 | 7.0 | 3:00:00 |
Goal times
What's a realistic goal?
Set your goal from current fitness, not wishful thinking. Use a recent half marathon or 10K as the anchor.
First marathon
Sub-5h (7:06/km). Finishing is the goal. Train at 7:30–8:15/km easy pace, peak at a 30 km long run.
Sub-4:30
6:24/km. Realistic for runners with a sub-2:10 half marathon. Need 4 sessions/week and one long run with M-pace blocks.
Sub-4:00
5:41/km. The big-ticket time barrier. Half marathon under 1:55 is the precondition. M-pace long runs are non-negotiable.
Sub-3:30
4:59/km. Solid amateur level. Half under 1:40, weekly 60–75 km, threshold + VO₂max blocks during build phase.
Sub-3:00
4:16/km. Competitive level. Half under 1:25, peak weekly 90–110 km, structured 16–20 week build with race-pace work.
Free with WattRun
AI-built marathon plan calibrated to your fitness and goal time. Adapts after every run. Free, no subscription.
Training paces
Pace zones around marathon pace
Race pace alone won't get you race-fit. Five training paces, derived from your goal marathon pace, that build the engine you need on race day.
Easy pace — 60-75 sec/km slower than M-pace
The bulk of your weekly mileage. Conversational, nasal-breathing only, heart rate under 75% of max. Goal: stress the aerobic system without raiding the recovery budget. Sub-4h marathoners run easy at 6:45-7:00 min/km; sub-3h marathoners at 5:15-5:30 min/km. If easy pace feels boring, that's correct.
Marathon pace (M-pace) — your goal pace
Built into long runs in 5-15 km blocks during the specific phase (last 8 weeks before the race). The 22-28 km long run with 16 km at M-pace is the single most marathon-specific session in any plan. Two sessions of M-pace work per week is the upper ceiling — more and you over-train without absorbing the load.
Threshold (T-pace) — 15-25 sec/km faster than M-pace
Lactate threshold work. Sustainable for 45-60 minutes in race effort, but used in training as 4-8 km blocks at "comfortably hard". The aerobic ceiling that determines how fast your M-pace can ever get. Once per week during the build phase, dropped during taper.
VO₂max — 60-75 sec/km faster than M-pace
Interval work at 3-5 minute reps with equal-time recovery. Builds aerobic ceiling. Less specific to marathon than threshold but useful in the base phase to lift the whole pace ladder. One session per week for 6-8 weeks, then drop in favour of threshold and M-pace.
Long-run pace — 30-60 sec/km slower than M-pace
The default pace for runs of 90+ minutes. Slower than easy because duration matters more than pace at this distance. The long run is the single biggest predictor of marathon success — more reliable than any tempo workout. Aim for 25-32 km in the 2-4 weeks of peak training, with M-pace blocks in the final 60 minutes.
Race day
Pace through the four phases of the marathon
The 42 km has predictable rhythm. Match your pacing to each phase and the wall stays behind you.
Phase 1 (km 0-5): Warm up, don't race
Run 5-10 sec/km slower than M-pace. The crowd is dense, adrenaline is high, and every runner who feels "fresh and easy" at km 3 is making the most common marathon mistake. Your body is still mobilizing fat oxidation — give it time. A 4:00 marathoner aiming for 5:41/km should run the first 5 km at 5:50/km.
Phase 2 (km 5-25): Lock onto goal pace
Settle into M-pace and hold it stable within ±3 sec/km per kilometer. This is the longest phase and the easiest to execute — fitness is fresh, glycogen is plentiful, and pacing is mostly about discipline. Check the watch every kilometer, don't trust the splits at hydration stations (positioning errors).
Phase 3 (km 25-35): The real race begins
Glycogen is now half-depleted; the mental game is starting. Hold M-pace, take a gel every 25-30 minutes, focus on form (cadence 175-180, slight forward lean). If you've trained well, this phase feels harder but pace stays stable. If you started too fast in phase 1, you'll slow here by 10-20 sec/km — the classic 30 km bonk.
Phase 4 (km 35-42.195): Empty the tank
The negative-split window. If pacing was disciplined, you have 5-15 sec/km in reserve. Push pace by 2-5 sec/km each kilometer, focusing on cadence rather than stride length (less injury risk when fatigued). Visualize finishing strong — mental imagery is documented to improve final-phase performance by 1-2%.
Race conditions
Adjust your target pace for the day
A flat Berlin marathon at 12°C is the gold standard. Anything different requires honest re-targeting.
Heat
Pace slows ~2 sec/km per 1°C above 15°C. A 25°C marathon costs roughly 20 sec/km — that's 14 minutes added to a 4:00 goal. Adjust target on race-week forecast, not race-day stubbornness. Race-week heat acclimation (sauna or extra layers on easy runs) buys back 3-5 minutes of that loss.
Hills
Net-elevation matters more than total elevation for marathon performance. 100 m net gain over the course costs about 1 minute on a 4:00 marathon. A hilly New York-style course costs 5-12 minutes versus a flat course at identical fitness. Don't compare PR times between Berlin and Boston.
Altitude
Above 1500 m, VO₂max drops 2-3% per 300 m of altitude. A Denver marathon (1600 m) is ~3% slower than sea level. Mexico City (2240 m) is 8-10% slower. The body adapts in 3-4 weeks of altitude living — short-term visits don't help.
Wind
Headwinds cost more than tailwinds gain — the asymmetry comes from drag scaling with wind speed squared. A 10 km/h headwind costs about 5-8 sec/km on flat terrain. In a stable point-to-point course like Boston, prevailing wind direction is the dominant weather variable.
More tools
Related calculators
Drill into specific marathon pace questions.
Marathon time predictor →
Predict marathon finish from a recent 5K, 10K, or half marathon. Riegel formula with full tables and accuracy ranges.
Half → Marathon conversion →
Convert half marathon pace to marathon pace. Why it's 15-25 sec/km slower, full conversion table, common pacing mistakes.
Min/mile ↔ Min/km converter →
Convert between min/mile and min/km, mph and km/h. With the full marathon pace conversion table.
FAQ
Frequently asked questions
How do I calculate my marathon pace?
Marathon pace = finish time in minutes ÷ 42.195. Example: a 3:30 finish is 210 min ÷ 42.195 = 4:58 min/km. The calculator above does this automatically — enter your finish time and read off the pace and full split table.
What is a good marathon time for beginners?
For first-time finishers, sub-5h (7:06 min/km) is a solid goal. Regular runners can aim for 4:00–4:30 (5:41–6:24 min/km). Advanced runners target sub-3:30 (4:59 min/km), competitive sub-3 (4:16 min/km). Even pacing or a small negative split matters more than the absolute time.
What is a negative split in marathon running?
Running the second half faster than the first. Example for a 3:30 marathon: first half in 1:46, second half in 1:44. The body conserves glycogen early and has reserves for the closing miles. Many world records have been set with negative splits — it's the optimal pacing strategy.
What pace do I need for a sub-4h marathon?
5:41 min/km — that's 10.55 km/h. Splits: 5 km in 28:25, 10 km in 56:50, half marathon in 1:59:30. Tip: start the first 5 km at 5:50 min/km and lock onto 5:41 from km 5 onwards.
How do I convert min/km to km/h?
km/h = 60 ÷ pace in minutes. Examples: 5:00 min/km = 12 km/h. 6:00 min/km = 10 km/h. 4:30 min/km = 13.3 km/h. The inverse is the same formula: min/km = 60 ÷ km/h.
What's the difference between pace and speed?
Both measure velocity but from opposite angles. Pace (min/km) tells you how long one kilometre takes — preferred in running. Speed (km/h) tells you how many kilometres you cover in an hour — preferred in cycling. The calculator shows both side by side.
Training plan
for your goal time
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