7 Professional Tools for Runners - VO₂ Max, Pace, Ultra Race Prediction, Age Grading, Elevation, Training Zones & Nutrition
Choose Your Calculator
VO₂ Max Calculator
Estimate your aerobic capacity using VDOT, FMR, or Cooper tests
Pace Calculator
Calculate your running pace, speed, and splits for any distance
Race Time Predictor
Ultra-accurate predictions from 5K to 100 miles with personalized calibration
Age Grading Calculator
Calculate age-graded performance based on WMA standards
Elevation Adjustment
Adjust race predictions for elevation gain and mountainous terrain
Training Zones
Calculate heart rate and pace zones for optimal training
Nutrition Calculator
Calculate calories, carbs, and hydration needs for your runs
VO₂ Max Calculator
What is VO₂ Max? VO₂ Max is the maximum amount of oxygen your body can utilize during intense exercise. It's measured in milliliters of oxygen per kilogram of body weight per minute (ml/kg/min).
Pace Calculator
Calculate your running pace, speed, and predicted finish times for various distances.
Race Time Predictor
Choose Your Mode: Quick mode uses one race time with standard adjustments. Advanced mode calibrates to YOUR physiology using two races for ultra-accurate predictions.
Age Grading Calculator
What is Age Grading? Age grading allows runners of different ages to compare performances fairly by adjusting for the natural decline in performance with age, based on World Masters Athletics standards.
Elevation Gain Adjustment Calculator
Why Elevation Matters: Hills and mountains dramatically impact race times. This calculator uses modified Naismith's Rule to adjust your flat-course predictions for elevation changes, giving you realistic times for trail and mountain ultras.
Training Zones Calculator
Train Smarter, Not Harder: Proper training zones prevent overtraining and maximize results. 80% of your running should be in Zone 2 (easy), with 20% in higher zones for quality work.
Nutrition & Hydration Calculator
Fuel Your Performance: Proper nutrition is critical for ultras. Running out of energy ("bonking") is the #1 reason people DNF. This calculator shows exactly how many calories and how much hydration you need.