Running Pace Calculator

Calculate running pace, finish time, and distance for any running workout.

Race Time Predictions

How It Works

Enter any two of three values (distance, time, or pace) to calculate the third. Convert between km/mile pace and see finish time predictions for common race distances.

**Running Pace Calculator — Train and Race with Precision**

Whether you're training for a 5K, half marathon, or ultramarathon, understanding pace is fundamental to running. Our Running Pace Calculator solves the three-way relationship between distance, time, and pace — enter any two, and it calculates the third.

**Three Calculation Modes**

1. **Pace from Distance + Time:** How fast are you running?
2. **Finish Time from Distance + Pace:** How long will a race take?
3. **Distance from Time + Pace:** How far did/will you run?

**Common Race Distances and Target Times**

| Distance | World Record | Sub-Elite | Average Recreational |
|---|---|---|---|
| 5K | 12:49 | <20 min | 25–35 min |
| 10K | 26:24 | <40 min | 45–60 min |
| Half Marathon | 57:31 | <1:30 | 2:00–2:30 |
| Marathon | 2:00:35 | <3:00 | 4:00–5:00 |

**Pace Zones for Training**

- **Easy/Recovery:** 60–70% max HR, conversational pace. Most training should be here.
- **Tempo:** 80–90% max HR, "comfortably hard," can speak in short phrases.
- **Interval:** 90–95% max HR, hard effort for 400m–1600m repeats.
- **Sprint:** 95–100% max HR, all-out effort for 100–400m.

**Pacing Strategy for Races**

The most effective race strategy for most runners is negative splitting — running the second half faster than the first. Starting too fast depletes glycogen and causes the "wall." Starting conservatively lets you finish strong.

**Pace vs. Speed**

- **Pace** — Time per unit distance (e.g., 5:00 per km)
- **Speed** — Distance per unit time (e.g., 12 km/h)

Our calculator supports both and converts between the two.

**Heart Rate vs. Pace Training**

For long-term development, training by heart rate (maintaining Zone 2) is more effective than training by pace. Pace varies with terrain, heat, and fatigue; heart rate adapts accordingly.

Frequently Asked Questions

A comfortable, conversational pace — typically 6:00–8:00 per km (9:40–12:52 per mile) — is appropriate for beginners. The key is being able to hold a conversation while running.
Speed (km/h) = 60 / pace (min/km). Then speed (mph) = speed (km/h) × 0.621. Example: 5:00 min/km = 12 km/h = 7.46 mph.
Running the second half of a race faster than the first half. Most world records are set with negative splits. It requires disciplined early pacing.
A rough predictor: Marathon time ≈ 10K time × 4.7. For example, a 50-minute 10K predicts approximately 3:55 marathon. Pete Riegel's formula (T2 = T1 × (D2/D1)^1.06) is more precise.
Cadence is steps per minute. Most elite runners maintain 170–180 spm. Higher cadence with shorter stride length reduces injury risk. Increasing cadence by 10% can improve running economy.