Marathon training utilities built by coaches
Plan smarter race efforts, model course difficulty, and share interactive tools with your athletes. Everything here is free to use online or embed in your team site.
Turn your finish time goals into precise mile and kilometer splits, share pacing charts, and embed the calculator anywhere.
- Race-day pacing
- Split projections
- Embeddable widget
Quantify race difficulty using elevation, weather, and course profile to fine-tune pacing plans and crew strategies.
- Course scoring
- Pacing adjustments
- Crew checklist
Predict your finish time for any distance based on a recent race result using the proven Riegel formula.
- Distance equivalents
- 5K to ultra predictions
- Confidence ratings
Find your Boston qualifying time, understand the cutoff buffer system, and calculate your realistic BQ target for 2026-2027.
- 2026-2027 standards
- Cutoff buffer guidance
- Downhill penalties
Get your VDOT score and all five Jack Daniels training pace zones from a recent race to optimize your training.
- Jack Daniels VDOT
- 5 training zones
- Race predictions
Plan your race nutrition with science-backed guidance. Calculate carbs, hydration, and electrolytes based on duration, weather, and your experience level.
- Race day fueling
- Carb loading plans
- Hydration timing
What we’re building next
Help us prioritize the next generation of MarathonOS tools—Pilot testers get early access and direct input into features.
Race Day Checklist
Build a customizable packing and logistics list for your crew and travel.