# Magic Mile Calculator (Galloway)

URL: https://speedycalculator.com/calculators/sports/magic-mile/
Last updated: 2026-10-30

> The magic mile calculator uses Jeff Galloway's method to predict your realistic race pace and finish time for a 5K, 10K, 10 miles, half marathon or marathon from a hard one-mile time trial.

## Inputs

- Magic mile time – minutes
- seconds
- Target race

## Results

- Predicted pace per mile
- Predicted pace per km
- Predicted finish time
- Average speed

## Formula

```
Pace per mile: 5K = mile + 33 s · 10K = mile × 1.15 · 10 mi = mile × 1.175 · Half marathon = mile × 1.2 · Marathon = mile × 1.3
```

## Explanation

The "magic mile" is a one-mile time trial run at your best sustainable effort. Galloway adds a margin for longer races, giving a conservative pace that most runners can actually hold.

### How to use the Magic Mile Calculator

- **Magic mile time – minutes**
- **seconds**
- **Target race**

Results update as you type, every field has its own unit menu, and everything is calculated in your browser.

### How it works

Enter your magic mile time and choose the race you are training for.

### Inputs explained

FieldWhat to enterMagic mile time – minutesA numbersecondsA numberTarget raceChoose one: 5K, 10K, 10 miles, Half marathon …

### What each result means

- **Predicted pace per mile** = [p]÷60
- **Predicted pace per km** = [p]÷1.609344÷60
- **Predicted finish time** = [p]×[d]÷1609.344
- **Average speed** = 1609.344÷[p]

## Worked example

Inputs — Magic mile time – minutes: 8; seconds: 0; Target race: Marathon.

Results — **Predicted pace per mile = 10:24**; Predicted pace per km = 6:28; Predicted finish time = 4:32:41; Average speed = 9.28 km/h.

## Key terms

- **Magic mile**: One-mile time trial used for pace prediction.

## FAQ

**How do I run a magic mile?**
Warm up, then run one mile (4 laps of a track) at a hard but controlled effort.

**How often should I repeat it?**
Every 2–3 weeks to track progress.

**Why is the marathon pace so much slower?**
Fatigue and fuel limits grow with distance.

**Is the prediction conservative?**
Yes – it is designed for finishing strong, not racing all-out.


## Sources

- [Jeff Galloway – Magic mile](https://www.jeffgalloway.com/training/magic-mile/)
- [Daniels' Running Formula (Jack Daniels, Human Kinetics)](https://us.humankinetics.com/products/daniels-running-formula-4th-edition)