RunSolver

RunSolver is the runner's toolkit — built for calculating, not tracking.

Whether you're planning a race, dialing in your splits, or predicting a finish time, RunSolver gives you fast, focused tools that work together. Enter your distance and time once, and every screen updates — pace, splits, predictions, and workouts all stay in sync.

PACE CALCULATOR Pick a distance or enter your own, set a finish time, and instantly see your pace, speed, and converted units. Clean, simple, no clutter.

SPLIT GENERATOR Generate per-km or per-mile splits with even, negative, or positive split strategies. Visualize your pace curve and share a race card image with friends.

RACE PREDICTOR Use the Riegel formula to predict finish times across distances — from the mile to 50K. Adjust for fitness level and see your age grade percentage.

WORKOUT BUILDER Choose from smart templates (intervals, tempo, long run, speed work) with paces derived from your target race time. Or build a fully custom workout and save it for later.

TOOLS

• Pace conversion (min/km to min/mi and back)
• Training pace zones from your threshold
• Treadmill speed to outdoor pace
• Boston Qualifier calculator
• Race comparison (planned vs actual)
• Personal records tracker

DESIGNED FOR RUNNERS

• Dark theme, clean interface
• Wheel pickers for fast time entry
• km/mi toggle everywhere
• Shareable race plan cards
• All calculations happen instantly — no loading, no accounts, no tracking

RunSolver is 100% free with no ads. Run the numbers.