Running Calculator
Enter a recent race result:
Race Splits
| Distance | Time | Pace/km | Pace/400m | Pace/mile | Speed m/s |
|---|---|---|---|---|---|
| --km | -- | -- | -- | -- | -- |
Race Predictor
| Distance | Time | Pace/km | Pace/400m | Pace/mile | Speed m/s |
|---|---|---|---|---|---|
| 800m | -- | -- | -- | -- | -- |
| 1000m | -- | -- | -- | -- | -- |
| 1500m | -- | -- | -- | -- | -- |
| 1 Mile | -- | -- | -- | -- | -- |
| 3km | -- | -- | -- | -- | -- |
| 5km | -- | -- | -- | -- | -- |
| 10km | -- | -- | -- | -- | -- |
| Half Marathon | -- | -- | -- | -- | -- |
| 30km | -- | -- | -- | -- | -- |
| Marathon | -- | -- | -- | -- | -- |
|
Custom Distance km |
-- | -- | -- | -- | -- |
Training Zones
| Zone | Pace/km | Pace/400m | Pace/mile | Speed m/s |
|---|---|---|---|---|
| 1 Recovery | -- - | -- - | -- - | -- - |
| 2 Endurance | -- - | -- - | -- - | -- - |
| 3 Tempo | -- - | -- - | -- - | -- - |
| 4 Threshold | -- - | -- - | -- - | -- - |
| Critical Speed | -- - | -- - | -- - | -- - |
| 5 VO2Max | -- - | -- - | -- - | -- - |
| 6 Anaerobic Capacity | -- - | -- - | -- - | -- - |
Enter a target distance and time:
Track Splits
| 400m Split | Pace/km | Pace/mile | Speed m/s | |
|---|---|---|---|---|
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
| -- | -- | -- | -- | -- |
Critical Speed
| Pace/km | D' | Pace/400m | Pace/mile | Speed m/s | Speed km/h |
|---|---|---|---|---|---|
| -- | --m | -- | -- | -- | -- |
Speed-Duration Curve
Frequently Asked Questions
A running calculator is a tool that estimates training paces
and predicts race times. For example, you can estimate your
expected half marathon time based on your 5km time. The track
calculator provides exact 400m track splits for a given target
time or pace. If you require more precision with your pacing
and training,
Chiron provides
in-depth performance metrics to help runners and coaches
optimise training.
Subscribe to
stay informed about the Chiron app release.
These calculations are estimates only based on a single race
result using the Peter Riegel race predictor formula. An
explanation of how these paces and race times are calculated,
its limitations as well as the source code can
be found here. For more accurate predictions, use the Critical Speed tab
to calculate your Critical Speed and D'.
Critical Speed (CS) lies somewhere between the Lactate
Threshold and VO2max. It represents the dividing line between
speed that could be sustained for a long time without fatigue
and effort which is so hard, you are forced to stop exercise
much sooner. The D' (or D-prime) tells us how energy can be
expended above Critical Speed before exhaustion. Read more
about
Critical Speed here.
The Speed-Duration Curve shows the hyperbolic relationship
between running speed and the duration until exhaustion. The
curve is based on your Critical Speed and D' values. The curve
shows the fastest speed you can maintain for a given duration.
It's easy to view your speed-duration curve, just enter two
recent race or time trial results into the Critical Speed tab
and hit Calculate.
Critical Speed (CS) is arguably the most important threshold
in long distance running. It is usually approximately the pace
you could sustain for a 30 to 40 minutes time trial on a 0%
grade flat surface or close to 10km pace for most runners. It
is an excellent predictor of performance. Estimating your
Critical Speed off a single race result using the running
calculator will work ok for most people. For more precision in
training and racing, it is recommended to calculate your
Critical Speed and D' values, which can be done by entering 2
recent time trial results into the calculator:
- A shorter duration, 2-6 minute time trial result (eg 800m - 1 mile)
- A longer duration, 12-25 minute time trial result (eg 5km)