1. What is the 5k to Half Marathon Time Calculator?

This calculator predicts your potential half marathon (21.1 km) time based on your current 5k (5 km) race time. It uses a well-established conversion factor to estimate longer distance performance from shorter race results.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• \( HM_{time} \) — Predicted half marathon time in minutes
• \( 5k_{time} \) — Your current 5k time in minutes
• 4.67 — Conversion factor based on average performance ratios

Explanation: The conversion factor accounts for the increased endurance demands of longer distances while maintaining similar intensity levels.

3. Importance of Race Time Prediction

Details: Accurate race time prediction helps runners set appropriate pace goals, plan training programs, and avoid starting too fast in longer races.

4. Using the Calculator

Tips: Enter your current 5k time in minutes (e.g., 22.5 for 22 minutes and 30 seconds). Use a recent race time for most accurate prediction.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this prediction?
A: It provides a reasonable estimate for runners with balanced speed and endurance. Those stronger in endurance may do slightly better, while speed-focused runners may find it challenging.

Q2: Does this account for training differences?
A: No, it assumes you've done equivalent training for both distances. More half marathon-specific training may improve your actual time.

Q3: Can I use a treadmill 5k time?
A: For best results, use an outdoor race time as treadmill running often produces slightly different performance.

Q4: What if my 5k time is very fast or slow?
A: Extremely fast runners may find the prediction slightly optimistic, while slower runners might beat the prediction as endurance becomes more dominant.

Q5: How should I use this prediction?
A: Use it as a guideline for pacing, but adjust based on course difficulty, weather conditions, and your specific strengths.