Per-KM Marathon Split Calculator
Build actual caller variable-pace segment split schedule including partial final kilometers; not scalar mean pace conversion or assumed even marathon pacing.
Description
A variable-pace split plan uses each segment’s own distance and pace.
A variable-pace split plan uses each segment’s own distance and pace. Partial final kilometers remain explicit.1
The returned values include Planned segment times seconds, Planned cumulative split seconds. The How section below explains the calculation, input rules and interpretation.
When to use Per-KM Marathon Split Calculator
Use Per-KM Marathon Split Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No even-marathon pacing assumption or completion guarantee is supplied.
Prepare the observed race, match or training records and the stated units. Supply independently verified rule editions, calibration tables and targets where requested.
How to use Per-KM Marathon Split Calculator and understand its results
- Prepare the observed race, match or training records and the stated units. Supply independently verified rule editions, calibration tables and targets where requested.
- Enter plannedKmSegmentDistances, plannedSegmentSecondsKm using the field table and calculation rules, then run the tool.
- Read plannedSegmentTimesSeconds, plannedCumulativeSplitSeconds. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| plannedKmSegmentDistances | Planned km segment distances | list of number | Required |
| plannedSegmentSecondsKm | Planned segment seconds km | list of number | Required |
Enter aligned nonempty positive kilometer segments and positive seconds/km. Return segment durations and cumulative splits.
segmentSeconds=km×secondsPerKm; splits=cumulative sum Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| plannedSegmentTimesSeconds | Planned segment times seconds | list of number |
| plannedCumulativeSplitSeconds | Planned cumulative split seconds | list of number |
{
"input": {
"plannedKmSegmentDistances": [
1,
1,
0.195
],
"plannedSegmentSecondsKm": [
300,
310,
320
]
},
"output": {
"plannedSegmentTimesSeconds": [
300,
310,
62.400000000000006
],
"plannedCumulativeSplitSeconds": [
300,
610,
672.4
]
}
}Limitations and assumptions
No even-marathon pacing assumption or completion guarantee is supplied.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Marathon Split Time To The Wall Calculator: A planned slowdown point separates two pace budgets. Its chosen distance need not mark physiological exhaustion. For a complementary task, use Riegel Race Time Prediction Calculator: Riegel scenarios extrapolate a race time with a caller fatigue exponent. Different historical races can yield different predictions.
References
-
Per-KM Marathon Split Calculator — tool.io
Similar or alternative tools
- Marathon Split Time To The Wall Calculator
A planned slowdown point separates two pace budgets. Its chosen distance need not mark physiological exhaustion.
- Riegel Race Time Prediction Calculator
Riegel scenarios extrapolate a race time with a caller fatigue exponent. Different historical races can yield different predictions.