Pace Calculator

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Race Pace Reference

Pace/km5K10KHalfMarathon
4:000:200:401:242:49
4:300:230:451:353:10
5:000:250:501:463:31
5:300:280:551:563:52
6:000:301:002:074:13
6:300:331:052:174:34
7:000:351:102:284:55

Race Distances

5K5 km / 3.1 mi
10K10 km / 6.2 mi
Half Marathon21.1 km / 13.1 mi
Marathon42.2 km / 26.2 mi

Understanding Running Pace

What is Pace?

Pace is the time it takes to cover a specific distance, typically expressed as minutes per kilometer (min/km) or minutes per mile (min/mi). Unlike speed (distance per time), pace tells you how long each unit of distance takes.

Pace vs. Speed

Pace: 5:00 /km
"I run one kilometer in 5 minutes"
Speed: 12 km/h
"I cover 12 kilometers per hour"

Pace = 60 / Speed (in km/h)

Race Time Predictions

While race times aren't perfectly predictable, there are formulas to estimate performance at different distances based on a known time. As distance increases, pace typically slows due to fatigue.

5K Time10KHalf MarathonMarathon
20:0041:301:32:003:12:00
25:0052:001:55:004:00:00
30:0062:302:18:004:48:00
35:0073:002:41:005:36:00

Training Paces

Different training runs should be done at different paces for optimal development:

Easy/Recovery Pace

60-90 seconds slower than race pace. Should be able to hold a conversation. Makes up 80% of training volume. Builds aerobic base.

Tempo Pace

"Comfortably hard" - about 25-30 seconds faster than easy pace. Sustainable for 20-40 minutes. Improves lactate threshold.

Interval Pace

Near race pace or faster for short repeats (400m-1600m). High intensity with rest periods. Improves VO2 max.

Race Pace

The pace you aim to maintain during your target race. Practice during specific workouts to build familiarity.

Pacing Strategy

Negative Split vs. Even Pacing

Negative Split:

Running the second half faster than the first. Recommended for marathons. Start conservatively, finish strong.

Even Pacing:

Maintaining the same pace throughout. Works well for 5K/10K. Requires good pace awareness.

Factors Affecting Pace

Terrain

  • • Hills slow pace by 15-30 sec/km
  • • Trail running is slower than road
  • • Sand/soft surfaces reduce speed

Weather

  • • Heat: add 1-2 min/km above 20°C
  • • Humidity increases effort
  • • Headwind slows you down

Fitness

  • • Training consistency
  • • Recovery and sleep
  • • Nutrition and hydration

Marathon Wall

Many runners experience "hitting the wall" around mile 20 (32 km) in a marathon when glycogen stores deplete. Proper training, pacing (don't start too fast), and fueling during the race can help prevent this. Starting 10-15 seconds per km slower than goal pace can help you finish stronger.

Frequently Asked Questions

What is a good running pace for beginners?

A comfortable beginner pace is typically 10-12 minutes per mile (6:15-7:30 per km). You should be able to hold a conversation while running. Focus on time on your feet rather than pace. As fitness improves, pace naturally increases. Many beginners complete their first 5K at 12-14 min/mile pace.

How do I convert pace between minutes per mile and minutes per kilometer?

To convert min/mile to min/km, divide by 1.609. For example, 8:00/mile divided by 1.609 = 4:58/km. To convert min/km to min/mile, multiply by 1.609. A 5:00/km pace equals about 8:03/mile pace. Most GPS watches can display either unit.

What is negative splitting and why is it recommended?

Negative splitting means running the second half of a race faster than the first. It's recommended because starting conservatively preserves energy, prevents early burnout, and allows you to finish strong. For marathons especially, running the first half 10-15 seconds per km slower than goal pace can significantly improve overall time and experience.

How can I predict my marathon time from my 5K time?

A common prediction method multiplies your 5K time by approximately 9.6 for marathon time. For example, a 25-minute 5K predicts a 4-hour marathon (25 x 9.6 = 240 minutes). However, this assumes proper marathon training. Shorter races don't fully prepare you for the marathon distance - specific long-run training is essential.