Running Pace Calculator
Know your pace per mile or kilometer, translate it to speed, and predict finish times for popular race distances — essential for pacing race day instead of blowing up at mile two.
Predictions assume even pacing and similar conditions. Real races add hills, weather, and crowds.
Pace vs speed
Runners talk pace (minutes per mile/km); the math is identical either way. Pick a target finish time for your next race, read the required pace, and train to hold it.
Race-day pacing tips
- Start 5–10 seconds per mile slower than goal pace — adrenaline lies.
- Negative splits (second half faster) beat positive splits almost every time.
- Practice goal pace in training so it feels automatic, not aspirational.
Frequently asked questions
What’s a good 10K pace?
It depends entirely on experience — 8:00/mile is strong for a beginner, while competitive amateurs run under 6:30/mile. Compare against your own history, not others.
How do I convert pace to speed?
Divide 60 by your pace in minutes per unit: a 5:00/km pace is 12 km/h.
Why did my predicted marathon time feel impossible?
Predictions assume perfect conditions and even pacing. Longer races punish aggressive early pacing — most runners fade 5–15% past 20 miles.
What pace should easy runs be?
Roughly 1–2 minutes per mile slower than 5K race pace — conversational, Zone 2 effort.
How often should I do speed work?
One to two quality sessions per week, with easy days between. More intensity without recovery just builds fatigue.