What if I train by heart rate instead of pace?

Treat pace as a secondary validation. If heart rate is unusually high for a given pace, adjust for heat, fatigue, or dehydration so the workout hits the intended zone.

How often should I update my goal pace?

Revisit pace targets after benchmark workouts or races. Improvements of 5–10 seconds per kilometre can influence fueling plans and workout prescriptions.

Calculator

Pace calculator.

Enter a distance and finish time to get your pace (per km and per mile) and speed. We’ll also show race‑distance finish times at that pace, plus examples and tips.

Calculate pace & speed

Distance (km)

Finish time (hh:mm:ss)

You can enter mm:ss (e.g., 50:00) or seconds (e.g., 3000).

Finish times at this pace

Distance	Time
1 km	—
1 mile	—
5 km	—
10 km	—
Half marathon	—
Marathon	—

How pace, speed, and finish time connect

Pace describes time per unit distance (minutes per kilometre or mile). Speed is the inverse — distance per unit time (kilometres per hour or miles per hour). Once you know any two of distance, time, and pace, algebra gives you the third. This calculator converts across units instantly and populates popular race-distance finish times so you can see how a goal pace plays out in the real world.

Because the tool outputs pace per kilometre and per mile simultaneously, you can reconcile workouts written in different systems. Enter track splits expressed in min/km, then copy the equivalent min/mile for your training log, or plug in marathon goals written in miles to get the kilometre pacing your watch expects.

Worked examples

Examples rounded to the nearest second.
Scenario	Inputs	Result
10K in 50:00	Distance: 10 km; Time: 00:50:00	Pace ≈ 5:00 /km (≈ 8:03 /mi); Speed ≈ 12.0 km/h
Half marathon in 1:45:00	Distance: 21.0975 km; Time: 01:45:00	Pace ≈ 4:59 /km; Finish marathon at this pace ≈ 3:29:00
5K at 8:00 /mi	Pace: 8:00 /mi	Finish time ≈ 24:52; Pace ≈ 4:58 /km
Trail race in 6:15 /km	Pace: 6:15 /km; Distance: 25 km	Estimated finish ≈ 2:36:15; Pace ≈ 10:03 /mi

Pace zones at a glance

Use the guide below to connect calculated pace with training intent. The exact numbers depend on your fitness, but the ranges illustrate how small changes in pace shift the physiological stress.

Adjust using heart-rate or perceived exertion if conditions are extreme.
Zone	Typical pace	Purpose	Coaching cue
Recovery	+60–90 s slower than marathon pace	Restore legs, maintain blood flow	“Conversation easy; keep strides light.”
Endurance	+30–60 s vs. marathon pace	Build aerobic base	“Smooth breathing, hold form for hours.”
Tempo / Threshold	Half-marathon to 1-hour race pace	Raise lactate threshold	“Comfortably hard, focus on rhythm.”
Interval / VO₂	3K–5K race pace	Develop maximal aerobic power	“Fast but controlled, full recovery between reps.”
Repetition	800 m race pace or faster	Sharpen neuromuscular efficiency	“Short reps, crisp mechanics, walk recoveries.”

Limitations & context

Real-world pace varies with terrain, elevation, temperature, wind, and fueling strategy.
Training paces differ from race paces — use heart-rate zones, perceived exertion, or power to validate effort.
Fatigue, cumulative training load, and psychological factors can alter sustainable pace even if the math says otherwise.

Related tools

Interpreting your pace

Add a distance and finish time to see a personalised explanation of your pace here. We’ll highlight equivalent speeds, typical training zones, and pacing strategy cues based on your entry.

Beyond the dynamic summary, review the suggestions below to translate the number into training intent:

Race simulations: match the predicted pace to your race distance and test fueling at that speed during long runs.
Workout planning: use the per-kilometre and per-mile outputs to script intervals (e.g., 4 × 1 km at 10K pace) with precise split targets.
Goal setting: adjust pace until the finish time aligns with your desired race, then reverse engineer the workouts needed to sustain it.

Retest when you log new benchmark performances or change surfaces (trail vs. road). Consistency between predicted and actual splits confirms that the pace you’re chasing is realistic.

Training playbook by pace goal

Use this guide to connect common race goals with weekly structure, fueling checkpoints, and supportive strength work. Adjust volume to suit your experience level.

Example week assumes a balanced program with at least one rest day.
Target finish	Average pace	Weekly focus	Key reminders
Sub-25 5K	4:59 /km · 8:00 /mi	Intervals (400–800 m), tempo run, long run 60–75 min	Fuel with light carbs before speed work; include hill sprints to build power.
Sub-50 10K	5:00 /km · 8:03 /mi	Progression runs, cruise intervals, weekend long run with final kilometres at goal pace	Practice even pacing — keep heart rate in control early, surge late.
Sub-1:45 half	4:59 /km · 8:02 /mi	Long run with steady-state block, midweek tempo, strides after easy runs	Dial in fueling every 30–35 minutes; rehearse race-day hydration.
Sub-4:00 marathon	5:41 /km · 9:09 /mi	Long run with pace segments, aerobic midweek medium-long run, strength twice weekly	Monitor fatigue — cap easy days at conversational pace to stay fresh.

Mix in cross-training if you notice form deteriorating at goal pace. Swimming, cycling, or elliptical sessions preserve aerobic gains without compounding impact.

Example use cases

Here are practical ways runners, coaches, and planners use the pace calculator during a season:

Race visualization: plug in goal times and export the pace table to a pace band so you can mentally rehearse each split before race day.
Training camp planning: coaches create shared sheets with paces for every athlete, grouped by ability, so interval workouts start on time and reduce congestion on the track.
Post-race analysis: enter the distance and finish time from your latest race to compare predicted vs. actual splits. Adjust pacing strategy (negative, even, positive) for the next attempt.
Route scouting: map a hilly course and test whether your target pace is realistic by simulating with treadmill incline adjustments or power targets.

Document environmental variables (temperature, elevation, terrain) when you log pace predictions. Those notes help explain discrepancies between calculated pace and field performance.

Workout ideas by pace

Use the outputs to build structured workouts. Below are templates you can adapt by slotting in the pace the calculator returns.

Speed development: 8 × 400 m at 5K pace with 200 m jog, preceded by drills and strides.
Threshold builder: 3 × 10 minutes at half-marathon pace with 3-minute jog recoveries.
Marathon rehearsal: 24 km long run with the final 8 km at goal marathon pace, practicing fueling timing.
Negative split practice: 12 km progression starting 45 seconds slower than marathon pace and finishing 15 seconds faster.
Cross-training support: 45-minute bike ride at equivalent aerobic intensity when legs need a break from pounding.

Pace calculator FAQs

Expand the accordions for quick answers on methodology, environment factors, and how to apply the results.

How does the calculator convert between pace and speed?

We normalise distance into kilometres, compute seconds per kilometre, and invert the value to derive km/h. For miles, we apply the 1.60934 conversion factor and repeat the same math so both units stay in sync.

Why do my splits drift on hilly courses?

Elevation changes alter power demands. Expect slower uphill splits and faster downhill splits for the same effort. Use grade-adjusted pace or power meters when terrain varies significantly.

How can I pace evenly without staring at my watch?

Set auto-lap alerts every 1 km or 1 mile, review the race table beforehand, and pair pace awareness with perceived effort cues like breathing cadence and stride rhythm.

What if I train by heart rate instead?

Use pace as a secondary check. If heart rate reads higher than expected for a given pace, heat, dehydration, or fatigue may be in play. Adjust effort so the session targets the intended zone.

How often should I update goal pace?

Recalculate after benchmark workouts (tempo runs, time trials) or races. Incremental improvements of 5–10 seconds per kilometre can change fueling strategies and workout prescriptions.

Pace & speed formula breakdown

The calculator works from the three-way relationship between distance, time, and rate. Once any two are known we solve for the third and display both metric and imperial equivalents.

Quantity	Formula used	Notes
Pace (per km)	pace_km = time ÷ distance_(km)	Returned as mm:ss by dividing seconds per km into minutes and seconds.
Pace (per mile)	pace_mi = time ÷ distance_(mi); distance is converted with 1 mile = 1.60934 km.	We derive mile distance first so that rounding differences stay under 0.1 s.
Speed (km/h)	speed_km/h = distance_(km) ÷ time_(hours)	Time in seconds is divided by 3600 to convert to hours.
Speed (mph)	speed_mph = distance_(mi) ÷ time_(hours)	Uses the same converted mile distance to keep results internally consistent.

Choosing your inputs

Distance + time (default) — plus: Works with any race or training segment, supports hh:mm:ss or raw seconds. Minus: Requires a known finish time; live pacing needs a watch split.
Known pace — plus: Enter pace directly (e.g., via quick buttons) and we infer time for any distance. Minus: Small pace entry errors propagate to all predictions.

All conversions happen at double precision and are rounded only when displayed, so copying the km pace into another tool and reconverting will match to within ±0.5 seconds.