Start with an honest scenario
Use a recent time or a pace you want to compare. The finish-time result assumes you sustain that pace; it does not predict readiness.
Switch calculator
MOVEMENT
Running pace calculator
Calculate pace, finish time, or distance.
Your pace and splits
Find a pace, finish time, or distance for your run.
Example · 5 km in 25:005:00 min/km
Save completed run on this device
Save only a run you completed. The date, distance, and time stay in this browser. They won’t sync, and clearing site data removes them.
THE RUN, BROKEN DOWN
Running splits
General information and estimates, not medical advice.
Use your result.
Take useful splits with you
Switch units, copy the summary, or download your splits. The last row includes the partial distance, so the full race is accounted for.
Build gradually
The NHS recommends warming up and building running progressively. For a first 5K, a structured beginner plan is more useful than chasing a calculator’s finish time.
BEHIND THE NUMBERSMethod & trusted reading
Your run.
A little clearer.
Pace is the time needed to cover one unit of distance. Choose any two of distance, time, and pace to calculate the third.
The simple maths
Pace = time ÷ distance. Time = pace × distance. Distance = time ÷ pace. One international mile is exactly 1.609344 km. We retain precision internally and round time only for display.
Splits that add up
Each row shows a kilometre or mile and your cumulative time. The final row includes any remaining partial distance. A half marathon is 21.0975 km; a marathon is 42.195 km.
A plan, not a prediction
Splits assume the same pace throughout. They do not account for hills, weather, stops, or fatigue. A finish time describes that pace over that distance, not what your body will achieve.
Formula references
Documented 9 November 2026. No clinical review is claimed.
Read further.
Original research and official guidance. References do not imply endorsement of HandyShelf.
NHS BEGINNER PLAN
A structured route to your first 5K ↗
The NHS Couch to 5K plan combines running and walking, building gradually across its programme.
National Health ServiceNHS PRACTICAL GUIDANCEWarm up and build running gradually ↗
Advice on preparation, progression, and common running problems. This is general guidance, not an assessment of an injury.
National Health ServicePUBLIC HEALTH GUIDANCEActivity beyond the finish time ↗
The CDC explains moderate and vigorous activity and how to spread activity through the week.
Centers for Disease Control and PreventionQuick questions.
How do I enter time?
Use minutes:seconds or hours:minutes:seconds. For example, 25:00 is 25 minutes; 1:45:00 is 1 hour 45 minutes.
Can I calculate finish time?
Yes. Choose “My finish time” and enter distance and pace. Or solve for distance from time and pace.
Can I save my splits?
Download a CSV table, copy the summary, or print the result. No account is needed.