Skip to content

Running Pace & Race Predictor

Convert pace ↔ time ↔ distance and predict your race times.

  • 🧮 Calculator
  • ✓ Free
  • ✓ No sign-up
  • ✓ Private — runs in your browser
  • ✓ Any device

Fill in any two of the three fields and the calculator solves the third. The most-recently-edited two are kept fixed.

hh : mm : ss
: :
:
speed

Race finish times at your current pace (), plus an even-pace split table.

Even-pace splits

Split Elapsed

Enter one recent race result and we'll predict the rest using Riegel's formula  T₂ = T₁ × (D₂ / D₁)^1.06.

Your known result

: :
Fatigue factor 1.06 = standard · lower = stronger endurance
pace / km
pace / mi

Why you’ll love Running Pace & Race Predictor

Instant & freeNo signup, no paywall, no limits — Running Pace & Race Predictor works the moment the page loads.
Completely privateEverything runs in your browser. Nothing you enter is ever uploaded or stored on a server.
Works on any deviceFully responsive and touch-friendly — use it on your phone, tablet or desktop.
Accurate & clearBuilt on the real formulas, with a breakdown you can actually trust.

How to use it

  1. 01

    Open it

    No download and no login — the tool is ready right at the top of this page.

  2. 02

    Use it

    Enter your details or start interacting. Everything updates live as you go.

  3. 03

    Get your result

    Copy, download or share your result in a single tap. That’s it.

About Running Pace & Race Predictor

A free running pace calculator and race time predictor that works entirely in your browser with no sign-up required. Convert between running pace, distance, and time instantly. Whether you're training for a 5K or marathon, this tool helps you understand your running speed and set realistic race goals without leaving your device.

Use this pace converter to translate between different units and time formats. Input any two of the three variables—pace, distance, or time—and the calculator solves for the third. Works with both metric and imperial measurements, making it useful whether you train in kilometers or miles.

The race predictor estimates your likely finish times across different distances based on your current performance. Plug in a recent race result or your typical pace, and see what you might achieve at other distances. Helps you set training targets and understand how fitness improvements translate to faster times.

Popular uses

  • ✦ Training for a 5K: calculate target paces for different run types based on your goal finish time
  • ✦ Planning a marathon: predict realistic finish times and adjust training based on current pace and distance
  • ✦ Converting between pace formats: quickly switch from minutes-per-mile to minutes-per-kilometer
  • ✦ Pacing strategy: determine splits and segment targets for long distances during a race
  • ✦ Fitness tracking: see how pace improvements over weeks or months translate to faster times at your goal distance

Frequently asked questions

What is running pace and how do I calculate it?
Running pace is the time it takes you to run one unit of distance, usually expressed as minutes per kilometer or minutes per mile. To calculate it, divide your total running time by the distance covered. A pace calculator automates this and lets you work backwards from pace to find distance or time.
How accurate is race time prediction?
Predictions are estimates based on mathematical models of running performance and assume consistent effort and conditions. They're most accurate for distances close to your recent race and less reliable for very different distances. Use predictions as rough guides rather than guarantees—actual performance depends on training, weather, and race-day conditions.
Can I use this with kilometers and miles?
Yes. The tool handles both metric and imperial units. Convert your pace to either system and calculate distances or times in whichever unit you prefer. This is especially useful if you train in one country's standard and race in another's.
What's the difference between pace and speed?
Pace and speed are inverses. Pace is time per distance (e.g., 6 minutes per km), while speed is distance per time (e.g., 10 km per hour). Both describe the same performance; this tool works with pace because that's how runners typically think about their running.
Is Running Pace & Race Predictor free to use?
Running Pace & Race Predictor is 100% free — no signup, no watermarks and no usage limits. It’s one of 200+ free tools we build and give away.
How accurate is this calculator?
It uses the standard formulas and shows its working, so you can verify every number. For big decisions, treat the result as a reliable estimate.

More calculators

All calculators
Pregnancy Due Date CalculatorEstimate your due date and see week-by-week milestones. Electricity Bill Calculator — Units & CostEstimate monthly electricity bills by entering units consumed and rate per kWh,... EMI Calculator — Home, Car & Personal LoanEMI calculator for home, car and personal loans: get monthly EMI, total interest...

People also use

Unit ConverterConvert length, weight, temperature, speed, area and digital storage instantly. Minesweeper Online — Play Free, No DownloadPlay Minesweeper online free — Beginner to Expert plus custom boards, first-clic... Free Resume Builder — No Signup, Print to PDFFree resume builder with live preview — make an ATS-friendly resume and save it...
Browse all 317 free tools

We built this. We can build yours.

Running Pace & Race Predictor is one of our free tools. Need a website, app, AI agent or automation? Fixed price — and you own the code.

Start a projectOur services