Distance Converter - Kilometers to Miles Calculator

Unit Converters

10K = 6.21 miles, 5K = 3.11 miles, Half Marathon = 13.11 miles, Marathon = 26.22 miles. Free distance converter for all race distances. Convert kilometers to miles instantly for running.

Kilometers

Miles

Distance Conversion

Equivalent distances in kilometers and miles

10 km ⟷ 6.214 mi

Quick Race Distance Conversions

10K in Miles

10K = 6.21 miles

5K to Miles

5K = 3.11 miles

Perfect beginner race distance

15K to Miles

15K = 9.32 miles

Popular intermediate distance

Half Marathon in Miles

21.1K = 13.11 miles

How many miles is half marathon?

Marathon in Miles

42.2K = 26.22 miles

How many miles is marathon?

How Far is a KM in Miles?

1 KM = 0.621 miles

Basic conversion factor

How to Use the Distance Converter

1. Enter your distance: Type any distance value in either kilometers or miles - the tool automatically converts to the other unit.

2. Use quick selectors: Click on common race distances (5K, 10K, half marathon, marathon) for instant conversion of popular running distances.

3. Plan your training: Use the conversions to follow international training plans, set GPS watch targets, or understand race distances when traveling.

Standard Race Distances

Understanding common race distances in both units helps with race planning and training:

Popular Race Distances

5K: 3.11 miles
10K: 6.21 miles
15K: 9.32 miles
Half Marathon: 21.1K = 13.11 miles
Marathon: 42.2K = 26.22 miles

Training Distances

1 mile: 1.61 kilometers
3 miles: 4.83 kilometers
5 miles: 8.05 kilometers
10 miles: 16.09 kilometers
20 miles: 32.19 kilometers

When to Use Each Unit System

Choose the right unit system based on your location, training goals, and race destinations:

Use Kilometers For:

International races: Most global races use metric distances
Track training: Standard track is 400m, making km calculations easier
European/Asian training: Following plans from metric-system countries
Smaller milestones: More frequent progress markers during long runs

Use Miles For:

US/UK racing: Many local races use mile-based distances
Road running: Mile markers are common on roads and paths
Traditional training: Classic training programs often use miles
Mental familiarity: If you think in miles for daily distances

Related Distance & Training Tools

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Calories Burned Calculator

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Medical Disclaimer

This calculator is for informational purposes only and is NOT medical advice. Results may be inaccurate. Always consult healthcare professionals before making health decisions.

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Frequently Asked Questions

How far is 10K in miles?

10K equals exactly 6.21 miles (6.2137 miles to be precise). This is the most popular running race distance worldwide. A 10K race is perfect for runners who have completed 5K races and want to challenge themselves with a longer distance without the commitment of a half marathon.

How many miles is 5K?

5K equals 3.11 miles (3.1069 miles exactly). The 5K is the most popular beginner race distance and takes most people 20-40 minutes to complete. It's an excellent starting point for new runners and a great distance for speed work for experienced runners.

How many miles is a half marathon?

A half marathon is 21.1 kilometers, which equals 13.11 miles (13.1094 miles exactly). This distance is exactly half of a full marathon and is a popular goal race for intermediate runners. It typically takes 1.5 to 3 hours to complete depending on fitness level.

How many miles is a marathon?

A marathon is 42.2 kilometers (42.195K exactly), which equals 26.22 miles (26.2188 miles precisely). This is the ultimate running challenge for most recreational runners, typically taking 3-6 hours to complete. The distance was standardized at the 1908 London Olympics.

How far is 15K in miles?

15K equals 9.32 miles (9.3206 miles exactly). The 15K is a popular intermediate race distance that bridges the gap between 10K and half marathon. It's challenging enough to require endurance training but short enough to maintain a relatively fast pace throughout.

How far is a kilometer in miles?

1 kilometer equals 0.621371 miles. This is the basic conversion factor used for all distance conversions. To convert any kilometer distance to miles, simply multiply by 0.621371. For quick mental math, you can use 0.62 as an approximation.

Why do some countries use kilometers while others use miles?

Most countries worldwide use the metric system (kilometers), while the United States, United Kingdom, and a few others primarily use the imperial system (miles) for road distances. In running, this means race distances like 5K, 10K, and marathons are often measured in kilometers globally, while some regions prefer miles for training and shorter races.

How do I convert my training paces between units?

When converting training plans between units, remember that pace also changes. A 6:00/mile pace equals approximately 3:44/km pace. Use our pace converter for accurate pace conversions, and our pace calculator to determine optimal training paces in your preferred unit.

What are the standard race distances in both units?

Common race distances: 5K = 3.11 miles, 10K = 6.21 miles, Half Marathon = 21.1K = 13.11 miles, Marathon = 42.2K = 26.22 miles. Many races also use mile markers (1 mile = 1.61K). Use our finish time predictor to estimate your performance across different race distances.

Should I train in kilometers or miles?

Train in the unit system you're most comfortable with or that matches your target races. If racing internationally, consider training in kilometers. If racing locally in mile-based regions, miles might be more intuitive. The key is consistency in your training log and understanding both systems for race planning.

How does distance unit choice affect my training?

The unit choice doesn't affect your actual fitness or performance, but it can impact your mental approach and pacing strategy. Some runners find kilometer splits more motivating (smaller, more frequent milestones), while others prefer the traditional mile markers. Choose what helps you stay motivated and track progress effectively. Monitor your energy expenditure regardless of unit choice.