pacvivo

Running Pace Calculator

Know your pace. Ship the race.

Convert pace, distance and finish time in seconds, then predict your next race off any recent result.

Pace Calculator

Pick with what you know.

Enter distance + running time.

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per km
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Race Time Predictor

Enter any recent race result. We predict the others with the Riegel formula (t₂ = t₁ × (d₂/d₁)^1.06).

Pace Table

Finish times for 5K, 10K, half and full marathon at common per-km paces (min per km).

Pace /km5K10KHalfMarathon

Why runners keep coming back to this

If you train in minutes per kilometer, most generic calculators force you to convert units before you get anything useful. pacvivo skips that friction entirely. Enter your distance and target time, and it hands back the exact min/km pace you need to hold. It suits recreational runners building race plans, coaches setting session targets, and anyone curious whether their last easy run actually stayed easy. No accounts, no ads cluttering the result — just the number you came for.

From distance to your target pace

  1. Enter the distance you plan to cover in the distance field.
  2. Type your goal finish time in hours, minutes, and seconds.
  3. Check that the unit selector reads kilometers before continuing.
  4. Click calculate to generate your pace per kilometer instantly.
  5. Read the result line and note the split for your session.

Frequently Asked Questions

How do I calculate my running pace?

Enter any two of pace, distance and finish time and the calculator works out the third instantly.

Can it predict my race times?

Yes. Using the Riegel formula, the calculator projects 5K, 10K, half-marathon and marathon times from any recent race result.

How accurate are the predictions?

The Riegel formula (t2 = t1 × (d2/d1)^1.06) is reliable for most runners over similar terrain and conditions. Adjust the result for hills, heat and a full taper.

Is the pace calculator free?

Yes — it is free, needs no sign-up and works on any device.

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