What is intervals.icu?
intervals.icu is a free training analysis platform built by David Tinker, a software developer and cycling enthusiast based in South Africa. It connects to your Strava account to provide deep performance analytics that rival paid platforms costing hundreds of dollars per year.
The platform has quickly become a favorite among data-driven cyclists and runners who want serious training tools without the subscription cost of TrainingPeaks or similar services.
Key Features
Fitness & Fatigue Modeling
The platform calculates your fitness (CTL), fatigue (ATL), and form (TSB) automatically from your training data. Watch your fitness build over time and optimize your training load to peak for events.
Power Analysis
For cyclists with power meters, intervals.icu provides detailed power curve analysis, training load tracking by power zones, and W' balance charts. Compare your power profile over different time periods and see how your fitness is developing.
Workout Builder
Create structured workouts with a visual editor. Build interval sessions, endurance rides, or complex training blocks, then export them to your head unit or sync them with other platforms.
Training Calendar
Plan your training weeks and months with a drag-and-drop calendar. Set weekly TSS targets, schedule workouts, and track your compliance with your training plan.
Who It's For
intervals.icu is ideal for:
- Self-coached athletes who want deep analytics without hiring a coach
- Data enthusiasts who love diving into performance metrics
- Budget-conscious athletes who can't justify expensive training platforms
- Cyclists and runners looking for better insights than Strava alone provides
How It Compares
While TrainingPeaks charges $120-200/year for similar features, intervals.icu offers comparable functionality for free. The main tradeoffs are:
- Less polished mobile experience (web-focused)
- Smaller community and fewer third-party integrations
- One-person development team (though very responsive)
For most self-coached athletes, these tradeoffs are easily worth the price difference.
