Riegel 1981 Cameron 2003 Jack Daniels VDOT Ely Temp Formula Altitude Corrected

Race Time
Predictor.

Five validated prediction models · Environmental adjustments for temperature, altitude, humidity & wind · Per-kilometre splits · HR training zones · India race nutrition strategy · Serial race log with fitness trend tracking.

🏃 5 Prediction Models 🌡️ Weather & Altitude ⏱️ Per-km Splits 🫀 HR Zones 📈 Race Log Tracker
5 Blended Models · Riegel + Cameron + VDOT
Temp · Altitude · Humidity · Wind Adjusted
WMA 2023 Age Grading · Karvonen HR Zones
India Race Nutrition · Taper Calculator

Race Time Predictor

Fill in your recent race performance → predict any target distance

Tip
For best accuracy: reference race within 50–100% of target distance, run within 8 weeks. Standard error ±3–8%. Error grows significantly when extrapolating >3× the reference distance (e.g. 5K → Marathon).
1 Athlete Profile
yrs
kg
bpm
Improves VO₂max estimate (Uth-Sørensen 2004)
km/wk
2 Reference Race Performance *
Recent = more accurate. >8 weeks = less reliable.
Hours
:
Minutes
:
Seconds
3 Target Race
4 Race Environment
m
0m = sea level · <600m minimal effect · >1500m significant
%RH
+1.5% per 10%RH above 60% (Martin 1992)
5 Race Strategy

Riegel 1981 · Cameron 2003 · Jack Daniels VDOT · Ely 2007 · Péronnet & Thibault 2001

PREDICTED RACE TIME
—
Select distances
Avg Pace
—
/km
Mile Pace
—
/mi
🟢 Best Case
—
🎯 Predicted
—
🟡 Conservative
—
VDOT
—
VO₂max
—
ml/kg/min
Age Grade
—
WMA 2023
Fitness
—
🌡️ Temp —
⛰️ Alt —
💧 RH —
💨 Wind —
HEART RATE ZONES — Karvonen
Enter age to see HR zones
Race Performance Log
No races logged yet

WHAT YOU GET

🎯
3-Range PredictionOptimistic / Predicted / Conservative
🌡️
Env. CorrectionsTemperature · Altitude · Humidity · Wind
📏
10-Distance EquivalentsFull VDOT table (1K → Marathon)
⏱️
Per-km Splits4 strategies with exact timestamps
🫀
HR Training ZonesKarvonen 5-zone + race day target HR
🥤
India Nutrition PlanPre/during/post + carb loading
📅
Taper Calculator4-phase periodisation with weekly targets
📈
Race Log & TrendTrack fitness gains over time

RACE DAY READY

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Nutrition Consult

Personalised race fuelling protocol, carb loading strategy, and post-race recovery plan from a registered sports dietitian.

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PREDICTION MODELS

Riegel (1981)T₂ = T₁ × (D₂/D₁)^e · most validated · 40% weight
Cameron (2003)Exponential model · better for long extrapolation · 35%
VDOT / DanielsVO₂max-based equivalents · Daniels 2013 · 25%
Temp (Ely 2007)+4% per 5°C above 15°C for marathon
Altitude (Péronnet 2001)VO₂max reduces ~1.2% per 100m above 1000m

TRY ALSO

🏥
NRI CalculatorNutritional Risk Index · 5 clinical indices
 🥧
Macro CalculatorTDEE · 12 diet presets · cycling
 🥩
Protein CalculatorActivity-based · ISSN 2017 · leucine

🏃 Predictions are estimates based on validated mathematical models. Individual performance varies based on training consistency, race-day conditions, health status, and pacing execution. Always consult a coach or sports medicine professional for personalised training advice. Riegel 1981 · Cameron 2003 · Daniels 2013 · Ely 2007 · Péronnet 2001.