🏃 Calculators

Running Pace Calculator

Convert pace (min/km) to speed (km/h) and compute total time for 5K, 10K, half-marathon and marathon distances. Useful for runners. Everything in your browser.

Pace (min/km)

Speed (km/h)

Times for classic distances

5 km

—

10 km

—

21,1 km

—

42,2 km

—

Running pace: formula and target paces

Pace is the time it takes to cover one unit of distance — by convention minutes:seconds per kilometre in Brazil and most of the world, or minutes per mile in the US and UK. The formula is pace = time_min / distance_km. Converting to speed: v_km/h = 60 / pace_min/km. Example: 50 minutes for 10 km gives a pace of 5:00/km, or 12 km/h. Target paces for the marathon: roughly 4:15/km for sub-3:00, 5:41/km for sub-4:00, 7:06/km for sub-5:00. Jack Daniels' VDOT tables and Pete Pfitzinger's plans translate a race time into training paces. Training zones: easy at 75-80% of max heart rate, threshold (tempo) at 88-92%, VO2max intervals at 95-100%.

Applications: training plans, races and apps

Used in Strava, Garmin Connect, Polar Flow and other tracking apps; in marathon and half-marathon training plans (Hal Higdon, Pfitzinger, Daniels); for pacing on the track (a 5:00/km pace means 2:00 per 400 m lap); and to set realistic race goals based on recent results. Negative splits — running the second half faster than the first — are the gold standard for marathons.

FAQ

Is pace the same as speed? They are inverses: pace is time/distance, speed is distance/time. A faster pace means a lower number (4:00/km is faster than 5:00/km).

How do I convert min/km to min/mile? Multiply min/km by 1.609. A 5:00/km pace equals roughly 8:03/mile.

What is a good 10 km pace? Highly individual. Beginners: 7:00-8:00/km. Recreational: 5:30-6:30/km. Sub-40-minute 10 km requires sub-4:00/km — a competitive amateur level.

Should every run be at the same pace? No. Most weekly mileage (around 80%) should be easy and conversational; only 20% should be quality work (intervals, threshold, long runs at marathon pace).

Running pace, speed and time

Every runner keeps an eye on pace, the rhythm in minutes per kilometre, but it isn't always simple to translate that into speed or to figure out how long a race will take. The calculator does that math for you, linking pace, speed and total time.

Enter your pace and see the equivalent speed in km/h, plus the estimated time for the classic distances (5K, 10K, half marathon and marathon). It helps you plan a workout, nail down a race goal or find out whether the pace you can hold meets the time you want to hit.

The calculation runs in the browser. Tweak the pace and all the times recompute at once, which helps you map out your race strategy.

Frequently asked questions

Can I enter a finish time and get the pace?

No, the flow runs one way only: you enter the pace in two fields, minutes from 0 to 20 and seconds from 0 to 59, and the page returns the speed and the four times. For the reverse, divide your target time in minutes by the distance. Forty-five minutes over 10 km gives 4.5 min/km, that is 4:30, and you can type it in to check. Zero out both fields and the calculation stops, leaving the last valid figures on screen instead of showing infinity.

Are the distances the official ones?

Yes, despite the rounded labels on screen. The half marathon goes in as 21.0975 km and the marathon as 42.195 km, so the figure matches the clock at a certified race. At a 5:00/km pace the marathon comes out at 3h 30min 59s rather than the flat 3h 30min you would get from a round 42 km. Speed is 60 divided by the pace in minutes, shown to two decimal places, so 5:00/km works out to 12.00 km/h.

Is the marathon time on screen realistic?

Treat it as an optimistic floor. The math multiplies one pace across every distance, which assumes an even effort from the first kilometre to the last, with no heat, no hills and no fatigue. Prediction models such as Riegel's formula put the drop in sustainable pace at roughly 4% each time the distance doubles, and the pace you hold over 5 km is not the pace you hold over 42. The 5K and 10K figures are the dependable ones for planning a session.

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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.