NN Marathon Rotterdam course & pace calculator
A fast, mostly flat course from Schiedamsedijk to Coolsingel, with two crossings of the Erasmus Bridge and a northern loop around Kralingse Bos. The profile follows the official 2026 route.
- Climb
- 86 m
- Descent
- 93 m
- Low – high
- -5 m – 13 m
- Terrain at 3:00
- +0:31
- Typical start
- 10°C
- Sub-3 needs
- 2:59:29 flat
Course time calculator
Type h:mm:ss or use the step buttons.
10°C at your start → 12°C at the finish · dew point 5°C
Heat is scored with shade WBGT from temperature and humidity, starting to cost time above about 15°C (59°F) WBGT. Slower runners lose more because they are out longer. Wind, sun and rain are not modelled.
Certified distance only. Switch on to count the metres lost to corners, crowds and aid stations.
Same effort all the way: slower up the climbs, faster down the descents.
- Flat course
- 2:59:29
- Terrain
- +0:31
- Weather
- ±0:00
- Rotterdam finish
- 3:00:00
Average 4:16 /km on course · 4:15 /km flat
Elevation profile
86 m up, 93 m down. Hover or tap the chart for the grade and your clock time at any point.
- Climb 2%+
- Climb 0.8–2%
- Flat
- Descent 0.8–2%
- Descent 2%+
- 1Schiedamsedijk · 0.0 km
- 2Erasmus Bridge, outbound · 0.4 km
- 3Erasmus Bridge, return · 27.1 km
- 4Coolsingel · 42.2 km
Course splits for 3:00:00
Even-effort splits with the selected weather. Climbing and descent are per split, from the smoothed profile.
| Split | Pace | Split time | Clock | Up / down |
|---|---|---|---|---|
| 1 km | 4:14 | 4:14 | 4:14 | +5 m / −12 m |
| 2 km | 4:18 | 4:18 | 8:33 | +4 m / −1 m |
| 3 km | 4:16 | 4:16 | 12:49 | +2 m / −2 m |
| 4 km | 4:15 | 4:15 | 17:04 | +0 m / −0 m |
| 5 km | 4:16 | 4:16 | 21:20 | +1 m / −1 m |
| 6 km | 4:13 | 4:13 | 25:33 | +0 m / −5 m |
| 7 km | 4:16 | 4:16 | 29:49 | +3 m / −2 m |
| 8 km | 4:16 | 4:16 | 34:05 | +1 m / −1 m |
| 9 km | 4:16 | 4:16 | 38:21 | +1 m / −1 m |
| 10 km | 4:14 | 4:14 | 42:35 | +0 m / −2 m |
| 11 km | 4:16 | 4:16 | 46:51 | +3 m / −3 m |
| 12 km | 4:16 | 4:16 | 51:07 | +1 m / −1 m |
| 13 km | 4:17 | 4:17 | 55:24 | +2 m / −0 m |
| 14 km | 4:15 | 4:15 | 59:38 | +1 m / −2 m |
| 15 km | 4:15 | 4:15 | 1:03:53 | +0 m / −1 m |
| 16 km | 4:17 | 4:17 | 1:08:10 | +4 m / −2 m |
| 17 km | 4:16 | 4:16 | 1:12:27 | +2 m / −0 m |
| 18 km | 4:16 | 4:16 | 1:16:42 | +2 m / −2 m |
| 19 km | 4:15 | 4:15 | 1:20:57 | +0 m / −1 m |
| 20 km | 4:15 | 4:15 | 1:25:13 | +1 m / −1 m |
| 21 km | 4:18 | 4:18 | 1:29:31 | +5 m / −3 m |
| 22 km | 4:16 | 4:16 | 1:33:46 | +2 m / −2 m |
| 23 km | 4:18 | 4:18 | 1:38:04 | +3 m / −0 m |
| 24 km | 4:16 | 4:16 | 1:42:20 | +2 m / −1 m |
| 25 km | 4:15 | 4:15 | 1:46:35 | +2 m / −4 m |
| 26 km | 4:16 | 4:16 | 1:50:52 | +3 m / −3 m |
| 27 km | 4:25 | 4:25 | 1:55:16 | +12 m / −3 m |
| 28 km | 4:11 | 4:11 | 1:59:28 | +0 m / −11 m |
| 29 km | 4:19 | 4:19 | 2:03:46 | +5 m / −2 m |
| 30 km | 4:13 | 4:13 | 2:07:59 | +0 m / −5 m |
| 31 km | 4:16 | 4:16 | 2:12:15 | +2 m / −1 m |
| 32 km | 4:17 | 4:17 | 2:16:33 | +3 m / −0 m |
| 33 km | 4:16 | 4:16 | 2:20:49 | +2 m / −1 m |
| 34 km | 4:12 | 4:12 | 2:25:00 | +0 m / −9 m |
| 35 km | 4:15 | 4:15 | 2:29:15 | +1 m / −2 m |
| 36 km | 4:18 | 4:18 | 2:33:33 | +3 m / −0 m |
| 37 km | 4:16 | 4:16 | 2:37:49 | +1 m / −0 m |
| 38 km | 4:16 | 4:16 | 2:42:05 | +1 m / −1 m |
| 39 km | 4:17 | 4:17 | 2:46:22 | +3 m / −1 m |
| 40 km | 4:15 | 4:15 | 2:50:37 | +1 m / −3 m |
| 41 km | 4:20 | 4:20 | 2:54:57 | +6 m / −0 m |
| 42 km | 4:14 | 4:14 | 2:59:11 | +0 m / −4 m |
| Finish | 4:13 | 0:49 | 3:00:00 | +0 m / −1 m |
Race-morning weather
Air temperature and relative humidity by hour from the first wave’s 10:00 start, from 104 mornings within three days of the race date since 2011 at ROTTERDAM, NL. Cool and warm are about the 10th and 90th percentile mornings by heat stress. Median wind 18 km/h.
| Local time | Cool | Typical | Warm |
|---|---|---|---|
| 10:00 | 6°C · 73% | 10°C · 72% | 13°C · 78% |
| 11:00 | 7°C · 65% | 10°C · 76% | 15°C · 72% |
| 12:00 | 7°C · 72% | 11°C · 75% | 17°C · 64% |
| 13:00 | 8°C · 59% | 12°C · 63% | 18°C · 55% |
| 14:00 | 9°C · 54% | 13°C · 59% | 19°C · 50% |
| 15:00 | 9°C · 49% | 13°C · 56% | 19°C · 54% |
| 16:00 | 8°C · 54% | 13°C · 56% | 20°C · 50% |
| Date | Start | +3 hours | Peak WBGT |
|---|---|---|---|
| 2025-04-13 | 13°C · 77% | 15°C · 71% | 17°C |
| 2024-04-14 | 12°C · 59% | 14°C · 57% | 15°C |
| 2023-04-16 | 8°C · 100% | 9°C · 96% | 14°C |
| 2022-04-10 | 8°C · 62% | 11°C · 45% | 13°C |
| 2019-04-07 | 13°C · 80% | 18°C · 62% | 20°C |
| 2018-04-08 | 15°C · 71% | 18°C · 66% | 20°C |
| 2017-04-09 | 13°C · 66% | 18°C · 51% | 19°C |
| 2016-04-10 | 10°C · 73% | 13°C · 52% | 14°C |
| 2015-04-12 | 10°C · 78% | 12°C · 60% | 14°C |
| 2014-04-13 | 11°C · 71% | 12°C · 66% | 14°C |
| 2013-04-14 | 13°C · 87% | 18°C · 65% | 20°C |
| 2012-04-15 | 9°C · 63% | 9°C · 58% | 11°C |
| 2011-04-10 | 10°C · 54% | 15°C · 48% | 17°C |
Data & method
- Route: Official NN Marathon Rotterdam 2026 GPX (https://nnmarathonrotterdam.nl/en/course/); Erasmus Bridge crests modeled at the city's published 17 m maximum road-deck height (https://www.rotterdam.nl/oeververbindingen). Measured at 42.11 km and scaled to 42.195 km.
- Elevation: Copernicus GLO-30 DEM (30 m), © DLR e.V. 2010–2014 and © Airbus Defence and Space GmbH 2014–2018, provided under COPERNICUS by the European Union and ESA. Sampled every 25–50 m, with bridges set to deck height and smoothed over 200–400 m.
- Weather: hourly observations from NOAA’s Integrated Surface Database (station 06344099999).
- Small climbs on flat courses can be terrain-model noise; they add only seconds to the estimates.
Frequently asked questions
Is the NN Marathon Rotterdam hilly?
The course climbs about 86 m (282 ft) and descends about 93 m in total, which is flat. At even effort the terrain alone changes a 3:00 flat-course marathon by +0:31 and a 4:00 by +0:41.
What flat-course time do I need to break 3 hours at the NN Marathon Rotterdam?
About 2:59:29 on a flat course, assuming a typical race morning. For a sub-4 you need about 3:59:19. Switch the weather off in the calculator to see the terrain-only figure.
What is the weather usually like at the NN Marathon Rotterdam?
On a typical race morning it is about 10°C (50°F) at the first wave’s start and 12°C (54°F) three hours later, with a dew point near 5°C. That costs a 3-hour runner about 0:00 and a 4-hour runner about 0:00. Figures come from airport observations within three days of the race date since 2011.
How is the course-adjusted time calculated?
The course is cut into 100 m pieces. Each piece is run at your flat-course pace times a grade factor (about +3.3% per 1% uphill and −1.8% per 1% downhill) and a heat factor from shade WBGT at the time you reach it. Adding the pieces gives the course time, and the calculator works backwards from a goal the same way.