Boston Marathon 2021
Boston · October 11, 2021 · 15,386 finishers
- Where the field cracked
- 30 km
- Negative splits
- 4.8%
- Median finish
- 3:45:13
- Finishers
- 15,386
Largest drop in pace between two mats.
Share of the field that ran the second half faster.
Fade, by finish time
Fade tracks ability, so a single field-wide median would compare you against people running a different race. Each band below is the median for runners who finished near your time.
| Band | Median fade |
|---|---|
| <3:00 | 4.9% |
| 3:00-3:30 | 7.4% |
| 3:30-4:00 | 11.0% |
| 4:00-4:30 | 16.9% |
| 4:30-5:00 | 21.1% |
| >5:00 | 23.0% |
Race conditions
- Temp.
- 15.2°C – 19.4°C
- Humidity at peak
- 81%
- Wind
- 11 km/h – 14 km/h
Temperature ran from 15.2°C to 19.4°C. At its hottest, the air was at 81% humidity.
Hour by hour
| Hour | Temp. | Humidity | Wind |
|---|---|---|---|
| 08:00 | 15.2°C | 94% | 11 km/h |
| 09:00 | 16.1°C | 92% | 13 km/h |
| 10:00 | 17.5°C | 87% | 13 km/h |
| 11:00 | 18.1°C | 86% | 13 km/h |
| 12:00 | 18.6°C | 84% | 14 km/h |
| 13:00 | 19.0°C | 82% | 13 km/h |
| 14:00 | 19.3°C | 80% | 11 km/h |
| 15:00 | 19.4°C | 81% | 12 km/h |
| 16:00 | 18.6°C | 84% | 14 km/h |
| 17:00 | 17.4°C | 87% | 13 km/h |
Hourly data from open-meteo. Peak wind 14 km/h. Times in the race's own zone.