Running pace calculator
Enter a distance and time to get your pace per mile and per kilometer, plus predicted times for other race distances.
How the race predictions work
Predictions use the Riegel formula: predicted time = your time × (new distance ÷ old distance)1.06. It's a widely used estimate that assumes you've trained for the longer distance, so treat marathon predictions from a 5K as optimistic unless your long runs are solid.
What should your easy pace be?
Most coaches put easy runs about 60–90 seconds per mile slower than your 5K race pace, or more. The better guide is heart rate: if you're in Zone 2 or can talk in full sentences, the pace is right, whatever the number says.
Train in Zone 2 with a coach in your ear
RunZone builds your plan around Zone 2, coaches you live with voice cues, and shows your pace getting faster at the same heart rate. iPhone, works with Apple Watch or just your phone.
Download RunZone