Cairn — GPX course preview and fuelling planner for ultramarathons and long trail races

Cairn

Read the course before you run it

or drag one anywhere onto this window

Parsed in your browser. Your file is never uploaded anywhere.

How Cairn works

  1. Upload your course Drag in the GPX your race organiser publishes. It is read in your browser and never uploaded.
  2. Read the climbs The route is coloured by gradient and split into climbs, descents and flats with distance, vert and average grade.
  3. Plan your fuelling Enter weight, target time and carbs per hour for a schedule placed by grade-adjusted effort, not spread evenly over distance.

How the pacing and fuelling maths works