๐Running Pace / Time Calculator
Enter any two of distance, time, or pace to get the third. Includes finish time predictions for 5K, 10K, half, and full marathon.
How to use
- 1Enter any two of distance, time, or pace.
- 2The remaining values calculate automatically.
- 3Check the projected 5K/10K/half/full splits.
FAQ
How accurate are the marathon predictions?+
Based on the Riegel formula, which estimates marathon time from your 5K pace. Real-world pace can be slightly slower, especially after 30km.
What does pace mean?+
The time it takes to run 1km (min:sec). '5:30/km' means 5 minutes 30 seconds per kilometer. Lower is faster.
What's a good beginner pace?+
When you're starting out, 6:30~7:30/km is reasonable. Running long and slow comes first; speed builds gradually.
What are sub-3 and sub-4?+
Finishing a full marathon in under 3 or 4 hours. Sub-4 needs about 5:41/km; sub-3 needs about 4:15/km sustained.
Is treadmill the same?+
Treadmills have no wind resistance and the belt assists you, making you about 0.5~1 min/km faster than outdoors. Adjust accordingly.
Can I calculate without a GPS watch?+
Just knowing your distance (one track lap = 400m) and time is enough. Many running courses publish distance markers โ check yours.