Cardiff Half Marathon
Cardiff, United Kingdom · Sunday 18 April 2027
The Cardiff Half Marathon is one of the largest and most exciting races in Wales, offering runners the chance to explore the capital city of Cardiff while running through its historic streets, parks, and along the Cardiff Bay. The course is mostly flat, with a few gentle inclines, making it a great race for runners of all levels. Along the way, participants will pass landmarks such as the Millennium Stadium, Bute Park, and the Cardiff Bay Barrage.
Difficulty Calculator
h
:m
:s
Adjusted Time
1:42:09
Time difference: -2.8 minutes compared to a flat, road, temperate course.
Course Details
Elevation Gain68m
Elevation High31m
Elevation Low8m
Weather Forecast
High14°C
Low9°C
Chance of Rain100%
How hard is Cardiff Half Marathon?
Easyharder than 10% of half marathons
Flattest / easiestHardest
On our difficulty model, Cardiff Half Marathon plays about 1 minute faster than an average road half marathon for a 1:30 runner. It ranks #403 hardest of 450 half marathons we analyse, and #81 of 89 in United Kingdom. Use the calculator above to see the exact adjusted time for your own goal pace.
What will you run at Cardiff Half Marathon?
Estimated finish times on this course versus the same effort on an average road half marathon, based on its elevation, surface, and expected race-day temperature.
| Average-course time | On Cardiff Half Marathon | Difference |
|---|---|---|
| 1:30:00 | 1:27:20 | −02:40 |
| 1:45:00 | 1:42:09 | −02:51 |
| 2:00:00 | 1:56:57 | −03:03 |
| 2:15:00 | 2:11:45 | −03:15 |
| 2:30:00 | 2:26:31 | −03:29 |
| 2:45:00 | 2:41:16 | −03:44 |
| 3:00:00 | 2:56:01 | −03:59 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Cardiff Half Marathon 2027 Course Analysis
Cardiff Half Marathon is a half marathon held in Cardiff, United Kingdom. It is scheduled for Sunday 18 April 2027. The course is run on road surface with 68m of total climbing, with its high point near 31m above sea level. For registration and full race details, visit the official Cardiff Half Marathon website.
Elevation Profile
This is a very flat course, with only 68m of total climbing and little change in altitude throughout. Flat profiles let you hold an even pace from start to finish, which makes this a fast, PB-friendly race.
Expected Race Day Weather
Based on historical weather data for April, the expected race day conditions are as follows. Near-ideal running temperatures are expected, ranging from 9°C to 14°C. This temperature range is widely considered optimal for marathon performance, allowing efficient heat dissipation without cold-related issues. There is a high chance of rain (100%). Runners should prepare for wet conditions, including appropriate footwear and clothing choices.
Surface Type: Road
Cardiff Half Marathon is run on road surfaces, which provide the fastest and most predictable conditions for racing. Road courses allow for consistent pacing and are typically the best choice for a personal best.
Looking for an easier marathon or a tougher challenge? You can also compare Cardiff Half Marathon against other half marathons to find the right race for your goals.
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If Cardiff Half Marathon fits your goal, these courses play out about the same on our difficulty model.
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