Courses · IRONMAN · Kona, USA
IRONMAN World Championship bike course
The 2026 course · Powered by blamethecourse.com
181.2 km measured along the road and 1104 m of climbing read off the ground, in 7 climbs.
- Distance
- 181.2 km
- Climbing
- 1104 m
- 6.1 m per km
- Climbs
- 7
- Longest climb
- 1.7 km
- averaging 2.6%, from km 6
- Steepest climb
- 4.7%
- average over 1.3 km, from km 126
Predict my bike split Your weight, your watts on each kind of road, road bike or TT bike: the course is already loaded, nothing to upload.
IRONMAN World Championship elevation profile
A model, not a measurement. What it can show depends on the numbers above — what you typed, and what your files recorded — and on assumptions this page states; anything it cannot stand behind says so rather than drawing a tidier line.
Road bike or TT bike?
89% of the IRONMAN World Championship bike course is road where an aero position does most of its work: 160.5 km between −3% and +3%. 2.2 km (1%) climbs at 5% or more, where most riders sit up. What a TT bike is worth to you depends on your watts and how aero you are on each bike, so the page does not guess: ride it both ways in the predictor and compare the two.
| Kind of road | How much | Up |
|---|---|---|
| Steep, above 5% | 2.2 km | 131 m |
| Climbing, 3 to 5% | 8.4 km | 326 m |
| Rising, 1 to 3% | 28.7 km | 547 m |
| Flat, −1 to 1% | 102.0 km | — |
| Falling, −3 to −1% | 29.8 km | — |
| Descending, −5 to −3% | 7.8 km | — |
| Dropping, below −5% | 2.2 km | — |
The same kinds of road the predictor asks about: there you set the watts you will hold and how you will sit on each.
The climbs of the IRONMAN World Championship bike course
- Climb, 1.2 km at 2.5%from km 2.0 · 29 m up
- Climb, 1.7 km at 2.6%from km 6.0 · 43 m up
- Climb, 1.0 km at 2.6%from km 11.0 · 27 m up
- Climb, 1.3 km at 2.8%from km 86.7 · 37 m up
- Climb, 1.3 km at 4.7%from km 125.5 · 60 m up
- Climb, 1.4 km at 2.2%from km 135.3 · 30 m up
- Climb, 1.5 km at 3.8%from km 150.0 · 56 m up
The road in the order you meet it
Each piece named by what the ground is: the climbs, the flats and the descents.
| Piece of road | Length | Slope | Rise |
|---|---|---|---|
| Flat, 2.0 km from km 0.0 | 2.0 km | — | 7 m |
| Climb, 1.2 km at 2.5% from km 2.0 | 1.2 km | 2.5% | 29 m |
| Flat, 2.8 km from km 3.2 | 2.8 km | — | — |
| Climb, 1.7 km at 2.6% from km 6.0 | 1.7 km | 2.6% | 43 m |
| Descent, 1.2 km at 3.3% from km 7.6 | 1.2 km | -3.3% | — |
| Flat, 2.2 km from km 8.8 | 2.2 km | -1.0% | — |
| Climb, 1.0 km at 2.6% from km 11.0 | 1.0 km | 2.6% | 27 m |
| Flat, 28.1 km from km 12.0 | 28.1 km | — | 54 m |
| Descent, 1.5 km at 3.9% from km 40.2 | 1.5 km | -3.9% | — |
| Flat, 13.3 km from km 41.6 | 13.3 km | — | 30 m |
| Descent, 1.4 km at 2.2% from km 54.9 | 1.4 km | -2.2% | — |
| Flat, 8.5 km from km 56.3 | 8.5 km | — | 33 m |
| Descent, 1.2 km at 4.8% from km 64.9 | 1.2 km | -4.8% | — |
| Flat, 20.7 km from km 66.0 | 20.7 km | — | 57 m |
| Climb, 1.3 km at 2.8% from km 86.7 | 1.3 km | 2.8% | 37 m |
| Flat, 15.4 km from km 88.1 | 15.4 km | — | 3 m |
| Descent, 2.6 km at 2.6% from km 103.5 | 2.6 km | -2.6% | — |
| Flat, 19.4 km from km 106.1 | 19.4 km | — | — |
| Climb, 1.3 km at 4.7% from km 125.5 | 1.3 km | 4.7% | 60 m |
| Flat, 8.5 km from km 126.8 | 8.5 km | — | — |
| Climb, 1.4 km at 2.2% from km 135.3 | 1.4 km | 2.2% | 30 m |
| Flat, 13.3 km from km 136.7 | 13.3 km | — | — |
| Climb, 1.5 km at 3.8% from km 150.0 | 1.5 km | 3.8% | 56 m |
| Flat, 29.7 km from km 151.5 | 29.7 km | — | — |
What bike split will you ride on the IRONMAN World Championship bike course?
This page describes the road; how long it takes depends on who rides it. Set your weight, the watts you will hold on each kind of road and how you will sit, and the predictor answers with your bike split and the band around it, climb by climb.
More courses like this one
How the road was measured
The length is measured along the mapped roads (OpenStreetMap), which all of the route followed, rather than along a GPS trace, which is longer or shorter than the road by however far its receiver wandered. The course file itself said 180.6 km, and a head unit measuring its own trace will read something close to that.
The climbing is read off a terrain model of the ground, averaged along the road, rather than off a barometer, which cannot tell a change in the weather from a hill. The file's own altimeter said 1003 m, near enough the same road.
The course as described from the course IRONMAN published for 2026. watts & time is not connected with the event or its organisers; a course changes from year to year, so check the current one before you plan on it.
Questions
How long and how hilly is the IRONMAN World Championship bike course?
181.2 km with 1104 m of climbing (6.1 m per km), in 7 climbs. The distance is measured along the mapped roads (OpenStreetMap) rather than a GPS trace, and the climbing is read off a terrain model of the ground rather than a barometer, which drifts with the weather, so a head unit will often show slightly different figures.
Is the IRONMAN World Championship bike course a course for a TT bike?
89% of it is road where an aero position does most of its work: 160.5 km between -3% and +3%. 2.2 km (1%) climbs at 5% or more, where most riders sit up. What a TT bike is worth to you depends on your watts and how aero you are on each bike: ride both in the predictor and compare the two.
What is the hardest climb on the IRONMAN World Championship bike course?
Climb, 1.3 km at 4.7%, from km 125.5: the most climbing in one go, 60 m.
Where are the climbs on the IRONMAN World Championship bike course?
In the order you meet them: Climb, 1.2 km at 2.5% from km 2; Climb, 1.7 km at 2.6% from km 6; Climb, 1.0 km at 2.6% from km 11; Climb, 1.3 km at 2.8% from km 86.7; Climb, 1.3 km at 4.7% from km 125.5; Climb, 1.4 km at 2.2% from km 135.3; Climb, 1.5 km at 3.8% from km 150.
What bike split can I expect on the IRONMAN World Championship bike course?
That depends on you, so this page does not guess: open the course in the predictor. Set your weight, the watts you will hold on each kind of road and how you will sit, on a road bike or a TT bike, and it answers with your bike split and the band around it, climb by climb. Nothing to upload: the course is already there.