Running7 min read

How To Find Your Half Marathon Pace

Calculate your ideal half marathon pace using race predictions and our free calculators. Learn pacing strategies and training approaches for your best 21.1K.

What's your half marathon pace? If you have a recent 5K or 10K time, you can predict it accurately. The half marathon is the perfect distance to challenge both speed and endurance—and finding the right pace is essential for success.

The half marathon (21.0975 km / 13.1 miles) has exploded in popularity because it's achievable for most runners yet challenging enough to require real training. Getting your pace right makes the difference between a strong finish and struggling through the final miles.

Step 1: Calculate Your Half Marathon Pace

The fastest way to find your half marathon pace is entering a recent race into our Running Interval Pace Calculator.

Here's the process:

  1. Enter your recent 5K or 10K time
  2. Get your predicted half marathon pace
  3. Also receive all your training paces (Easy, Marathon, Threshold, Interval)

This uses validated race equivalency formulas that account for the aerobic and anaerobic demands of different distances.

Half Marathon Pace Predictions

From Your 5K Time

5K TimeHalf Marathon PaceHalf Marathon Finish
18:004:00 min/km1:24:22
20:004:28 min/km1:34:10
22:004:55 min/km1:43:34
24:005:22 min/km1:53:06
25:005:36 min/km1:57:52
27:006:02 min/km2:07:25
30:006:42 min/km2:21:18

From Your 10K Time

10K TimeHalf Marathon PaceHalf Marathon Finish
38:004:05 min/km1:26:05
42:004:31 min/km1:35:17
45:004:50 min/km1:41:48
48:005:09 min/km1:48:45
50:005:22 min/km1:53:03
55:005:54 min/km2:04:27
60:006:27 min/km2:15:49

Use our Half Marathon Pace Calculator to find the exact pace for your goal time.

Step 2: Verify With the Pace to Time Calculator

Once you have your pace, confirm your finish time with our Pace to Half Marathon Time Calculator.

This helps with race planning:

  • Set realistic goals
  • Plan split times
  • Calculate pace bands for your watch

How Half Marathon Pace Relates to Training Paces

Your half marathon pace sits between marathon pace and threshold pace:

Pace TypeRelative to HM PacePurpose
Easy Pace45-75 sec/km slowerRecovery, base miles
Marathon Pace10-20 sec/km slowerLong runs, endurance
Half Marathon PaceGoal race paceRace, specific workouts
Threshold Pace5-10 sec/km fasterTempo runs
Interval Pace30-45 sec/km fasterVO2max work

Get all these paces from one race time using our Running Interval Pace Calculator.

Half Marathon Pace Workouts

Tempo Runs at Half Marathon Pace

  • Workout: 8-12km at goal half marathon pace
  • Purpose: Build confidence and efficiency at race pace
  • When: Weekly during specific preparation phase

Half Marathon Pace Intervals

  • Workout: 4-6 × 2000m at HM pace with 2-minute recovery
  • Purpose: Develop ability to hold pace while slightly fatigued
  • When: Every 7-10 days

Progression Long Runs

  • Workout: 18-22km starting easy, final 6-10km at HM pace
  • Purpose: Practice race execution, negative splitting
  • When: Every 2-3 weeks

Example Week (12 Weeks to Race)

DayWorkoutPace
MondayRest-
Tuesday6 × 1000m with 90s restInterval Pace
Wednesday8km easyEasy Pace
Thursday10km tempoHM Pace
FridayRest or 5km easy-
Saturday18km long runEasy to Marathon Pace
Sunday6km recoveryEasy Pace

Adjusting Pace for Race Day Conditions

Your predicted pace assumes good conditions. Adjust accordingly:

Temperature Adjustments

ConditionsPace Adjustment
5-12°C (41-54°F)Optimal - use goal pace
13-18°C (55-64°F)Add 3-5 sec/km
19-24°C (66-75°F)Add 8-15 sec/km
25°C+ (77°F+)Add 15-25+ sec/km

Course Adjustments

Course ProfileAdjustment
FlatUse goal pace
Rolling hillsAdd 5-10 sec/km average
HillyAdd 10-20+ sec/km average
Net downhillSubtract 3-5 sec/km

Half Marathon Pacing Strategies

Even Pace Strategy

Run consistent pace throughout. This works well for experienced runners on flat courses.

Execution: First 5km slightly conservative (3-5 sec/km slow), then settle into goal pace.

Negative Split Strategy

Run the second half faster than the first. This is often the fastest way to race.

Execution:

  • 0-10.5km: 5-8 sec/km slower than goal
  • 10.5-16km: At goal pace
  • 16-21.1km: At or slightly faster than goal

Conservative Start Strategy

Best for first-timers or uncertain conditions.

Execution:

  • First 5km: 10-15 sec/km slower
  • Middle 11km: At goal pace
  • Final 5km: Whatever you have left

Common Half Marathon Pacing Mistakes

Starting Too Fast

The first few kilometers feel deceptively easy. Going out 15 seconds per kilometer too fast can cost you several minutes by the end.

Ignoring the Hills

Running the same pace uphill as on flat ground burns energy disproportionately. Run by effort on hills, recover on descents.

Chasing Others

Your race is against the clock, not other runners. Stick to your plan even if others go out faster.

Dehydrating

At half marathon pace, you'll need fluids. Practice drinking at race pace during training.

From Finish Time to Pace

Use our Half Marathon Pace Calculator for precise conversions:

Goal TimeRequired Pace (min/km)Required Pace (min/mile)
1:20:003:486:07
1:30:004:166:52
1:40:004:447:38
1:45:004:588:00
1:50:005:128:23
2:00:005:419:09
2:15:006:2410:18
2:30:007:0611:27

Training Plan Structure

A typical half marathon training plan is 10-14 weeks:

Weeks 1-4: Base Building

  • Build mileage gradually
  • All running at easy pace
  • One long run per week (12-16km)

Weeks 5-8: Development

  • Introduce tempo runs at half marathon pace
  • Add interval sessions
  • Long runs reach 16-18km

Weeks 9-12: Specific Preparation

  • Half marathon pace workouts become primary focus
  • Practice race fueling and hydration
  • Long runs reach 18-21km with goal pace segments

Weeks 13-14: Taper

  • Reduce volume by 30-50%
  • Maintain intensity
  • Stay fresh for race day

Calculate Your Calorie Burn

Planning your nutrition? Use our Half Marathon Calorie Calculator to estimate energy expenditure.

A typical half marathon burns:

  • 60kg runner: ~1,200-1,400 calories
  • 70kg runner: ~1,400-1,600 calories
  • 80kg runner: ~1,600-1,800 calories

This helps you plan pre-race fueling and during-race nutrition.

Find Your Half Marathon Pace Now

Ready to find your pace? Here's the process:

  1. Get Your Predicted Pace: Enter a recent race at Running Interval Pace Calculator

  2. Check Your Finish Time: Use Half Marathon Pace Calculator

  3. Plan Your Split Times: Use Pace to Half Marathon Time

  4. Estimate Calories: Plan nutrition with Half Marathon Calorie Calculator

Your half marathon pace is the foundation of effective training. With the right goal and structured preparation, you'll cross that finish line feeling strong.

For a complete training approach, check out our 12 Week Half Marathon Training Plan.

Visit our Running Calculators hub for all our free running tools.

Disclaimer: Information provided by this site is for educational purposes only and is not intended to be a substitute for professional medical advice specific to the reader's particular situation. The information is not to be used for diagnosing or treating any health concerns you may have. The reader is advised to seek prompt professional medical advice from a doctor or other healthcare practitioner about any health question, symptom, treatment, disease, or medical condition.