Training Pace Calculator
Calculate your optimal training paces based on recent race results using scientific models.
Input Guide
A field-by-field walkthrough of every input in the Training Pace Calculator — what it does, which options to choose, and how different values affect your results.
Prediction Model
radioSelect which scientific model to use for computing your training zones. Each model uses a different mathematical approach to estimate fitness from race data, and each has different accuracy profiles depending on your training history and the number of race results you provide.
Options
If you have two or more recent race results at different distances, the Hybrid model is the most accurate because it captures your individual fatigue profile rather than assuming a population average.
Race Distance
selectChoose a standard race distance from the dropdown or select "Custom" to enter any distance in kilometres or miles. Standard distances (1500m, Mile, 5K, 10K, 15K, Half Marathon, Marathon) have built-in conversions. For Critical Speed and Hybrid models, the accuracy improves when the races you enter span a wide distance range — e.g., a 5K and a half marathon rather than two 10Ks.
Options
For the most accurate Critical Speed calculation, use races that are at least 2× apart in distance — for example, a 5K and a half marathon.
Finish Time
numberEnter your race finish time in hours, minutes, and seconds. The fields auto-advance when you type two digits, so you can tab through quickly. Use a recent race (past 4–8 weeks) run at full effort for the most accurate results — an old PR or a training run will skew your zones.
If you ran a parkrun in 25:30, enter 0 hours, 25 minutes, 30 seconds. The calculator accepts times from a few minutes to several hours.
Temperature
numberThe temperature at your training location, in Celsius or Fahrenheit. Above 10°C, the calculator applies a 0.3% pace penalty per degree. Below 10°C there is no penalty — cooler conditions are considered baseline. This field is optional; leave it blank to calculate without heat adjustment.
Options
Humidity
numberRelative humidity as a percentage. Above 50%, the calculator applies a small additional penalty (0.1% per percentage point). High humidity reduces your body's ability to cool through evaporation, effectively making the heat feel worse. Combined with high temperature, humidity has a compounding effect on the pace multiplier.
Options
Altitude
numberElevation above sea level in meters or feet. Above 1500m (4921ft), the calculator applies a 1% penalty per 300m of additional elevation. At altitude, reduced oxygen partial pressure means your aerobic system works harder at any given pace. This adjustment is separate from heat and humidity — all three compound multiplicatively.
Options
Calculate Your Training Paces with Four Scientific Models
The Training Pace Calculator is the core tool on myRunningPace. Enter one or more recent race results and instantly receive six personalised training zones — from easy recovery jogs to VO₂max intervals — using your choice of four peer-reviewed prediction models. Unlike single-model calculators, you can switch between VDOT, Riegel, Critical Speed, and our Hybrid blend to see how each model interprets your fitness.
What Is the Training Pace Calculator?
This calculator takes your race results and runs them through a scientific prediction model to compute your estimated VO₂max and six training zones (Recovery, Easy, Long Run, Tempo, VO₂max, Repetition). Each zone is expressed as a pace range in your preferred unit (per km or per mile). Optionally, you can add temperature, humidity, and altitude to see how environmental conditions shift your target paces. The entire calculation runs in your browser — no data is sent to any server.
Why Use a Training Pace Calculator?
- Get six personalised training zones from a single race result — no coaching certification required
- Compare four prediction models side by side: VDOT Classic, Riegel, Critical Speed, and Hybrid
- Automatically adjust paces for heat, humidity, and altitude using published environmental correction factors
- Detect whether you favour speed or endurance when you enter two or more race results
- See confidence ranges that show best-case to conservative pace estimates for every distance
- Free, instant, and private — calculations happen entirely in your browser
Who Uses the Training Pace Calculator?
Self-coached runners
Get the same scientifically prescribed paces that a certified coach would calculate — using the VDOT model from Daniels' Running Formula.
Marathon and half marathon runners
Use multiple race results with the Hybrid model for the most accurate long-distance pace prescription. Add environmental conditions if training in heat.
Beginners building a base
Find your Easy and Recovery zones to avoid overtraining. A 30:00 5K runner gets an Easy pace of about 7:30/km — much slower than most beginners expect.
Track and speed-focused athletes
The Repetition zone (105% VO₂max intensity) gives you the pace for short, fast intervals that develop running economy and neuromuscular speed.
Runners training at altitude or in heat
The environment adjustment shows exactly how much to slow down. At 30°C and 60% humidity, the calculator applies a ~1% pace correction automatically.
Coaches prescribing group workouts
Quickly generate individualised zones for multiple athletes using their most recent race results. Switch between models to find the best fit for each runner.
Under the Hood
The mathematical models and algorithms that power each calculation — sourced directly from published sports science research.
VDOT Oxygen Cost Model
The VDOT Classic model uses the Daniels/Gilbert formula: VO₂ = −4.60 + 0.182258v + 0.000104v² (where v is velocity in m/min) to estimate oxygen cost, then divides by the percent of VO₂max sustainable at that race duration to compute your VDOT score. Six training zones are derived by solving the quadratic at specific intensity fractions (60%–105%).
Riegel Power-Law Formula
Peter Riegel's 1977 formula T₂ = T₁ × (D₂ / D₁)^1.06 scales a known race time to any other distance using a single exponent (k = 1.06). The exponent encodes how fatigue accumulates with distance. This model is simple and effective for quick estimates but assumes a population-average fatigue profile.
Critical Speed Linear Regression
Given two or more race results, Critical Speed is calculated as the slope of the distance-vs-time regression line: CS = (D₂ − D₁) / (T₂ − T₁). With three or more races, least-squares linear regression is used for a more robust estimate. The y-intercept gives anaerobic capacity (D'), representing finite energy above critical speed.
Hybrid Blend (60/40)
The Hybrid model combines VDOT (60% weight) with Critical Speed (40% weight) using a scaling factor of 11.25 to normalise CS values (typically 3–5.5 m/s) into the VDOT space (typically 30–85). This produces a blended fitness score that leverages both the oxygen cost model and your individual fatigue profile.
Privacy
Every calculation runs entirely in your browser using client-side JavaScript. Your race times, body data, and training zones are never transmitted to or stored on any server. There are no analytics trackers on calculator inputs.
Example Scenarios
Real inputs and the exact output from the engine — so you know what to expect before you start.
Beginner 5K Runner
A runner finishing 5K in 30:00 using the VDOT Classic model receives a VO₂max estimate of 30.8, an Easy pace of 7:30/km, and a Tempo pace of 6:16/km. These paces are deliberately slow — most beginners overtrain by running their easy days too fast.
VDOT 30.8 · Easy 7:30/km · Tempo 6:16/km
Competitive 10K Runner
A 42:00 10K (4:12/km pace) on the VDOT Classic model yields an estimated VO₂max of 49.1 and an Easy zone of 5:12/km. This runner is solidly in the "intermediate" fitness classification and would benefit from structured tempo and interval work.
VDOT 49.1 · Easy 5:12/km · 10K pace 4:12/km
Sub-3 Marathoner
A 2:55:00 marathon (4:09/km pace) produces a VDOT of 55.3 and an Easy pace of 4:43/km. At this fitness level, the gap between Easy and Marathon pace is less than 35 seconds per kilometre — precision in zone adherence matters significantly.
VDOT 55.3 · Easy 4:43/km · Marathon 4:09/km
Research & References
Training-zone calculations in this tool are grounded in peer-reviewed exercise physiology.
- Daniels, J. (2013). Daniels' Running Formula (3rd ed.). Human Kinetics.
- Riegel, P. S. (1981). Athletic Records and Human Endurance. American Scientist, 69(3), 285–290.
- Jones, A. M., & Vanhatalo, A. (2017). The "Critical Power" Concept: Applications to Sports Performance. European Journal of Sport Science, 17(10), 1275–1284.
Frequently Asked Questions
Related Calculators
Race Time Predictor
Enter one race result to predict your finishing time for any distance — from 1500m to marathon.
VO₂max Estimator
Estimate your VO₂max from a recent race performance.
Heat Adjusted Pace Calculator
Enter your base pace and race-day conditions to see how heat, humidity, and altitude affect your target splits.