Triathlon Finish Time Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
Result
Enter a pace or speed for each leg to see your finish time and splits.
Estimate only — real results depend on course, weather, terrain, fatigue, transitions, equipment, nutrition and event rules. Not medical or coaching advice.
How to use this calculator
- Choose your event (Super Sprint, Sprint, Olympic/Standard, Half Distance 70.3, Full Distance 140.6, or Custom).
- Enter your swim pace (per 100 m), bike speed (km/h), run pace (per km) and T1/T2 transition times.
- Read your estimated finish time and per-leg splits — or switch to Target Finish to solve the pace you need for a goal time.
How it works
Each leg is timed from your effort: swim = (distance ÷ 100) × pace per 100 m; bike = (distance ÷ speed) × 3600; run = distance × pace per km. Transitions are added as entered. The total is the sum of all legs plus transitions.
Target Finish mode reverses it: required leg time = target − (other legs + transitions), then converts that time into the pace or speed you'd need.
Worked example
Sprint triathlon. 750 m swim @ 2:00/100 m (15:00), 20 km bike @ 30 km/h (40:00), 5 km run @ 5:00/km (25:00), T1 3:00 + T2 2:00 = 1:25:00 total.
Tips
- Times are estimates only — not medical or coaching advice. Always train safely and follow event rules.
- Distances are editable: choose “Custom…” to enter your own course lengths.
- Zerdly is not affiliated with World Triathlon or IRONMAN; 70.3 and 140.6 are used as neutral distance labels.
Frequently asked questions
What are the standard triathlon distances?
Sprint ≈ 750 m / 20 km / 5 km; Olympic/Standard ≈ 1.5 km / 40 km / 10 km; Half Distance (70.3) ≈ 1.9 km / 90 km / 21.1 km; Full Distance (140.6) ≈ 3.8 km / 180 km / 42.2 km. Organisers vary courses, so all distances are editable.
How accurate are these times?
They're estimates. Real race times depend on terrain, weather, elevation, fatigue, transitions, nutrition, equipment, drafting and water conditions. Use them for planning and pacing, not as a guarantee.
Do my inputs get uploaded?
No. Everything is calculated in your browser — nothing is sent to a server or stored.
What is Target Finish mode?
Enter a goal finish time and the paces/speeds for the other legs, then pick the leg to ‘solve for’. The calculator works out the pace or speed you'd need on that leg to hit your goal.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.



