Traffic peak-hour factor calculator

Calculate peak-hour factor and peak subinterval count with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use peak-hour factor and peak subinterval count to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Traffic counts per equal subinterval (vehicles)
100,150,180,120
Subinterval duration (minutes)
15
Peak-hour factor
0.763889
Peak subinterval count (vehicles)
180
Hourly observed count (vehicles)
550

Try another scenario

Traffic counts per equal subinterval (vehicles)
[101, 150, 180, 120]
Subinterval duration (minutes)
15
Peak-hour factor
0.765278
Peak subinterval count (vehicles)
180
Hourly observed count (vehicles)
551
Calculation method

Calculation method

Peak-hour factor

One full hour of equal subintervals; PHF=hour count/(intervals per hour×largest interval count).

Peak subinterval count (vehicles)

One full hour of equal subintervals; PHF=hour count/(intervals per hour×largest interval count).

Hourly observed count (vehicles)

One full hour of equal subintervals; PHF=hour count/(intervals per hour×largest interval count).

Symbols and units
a
Traffic counts per equal subinterval (vehicles)
b
Subinterval duration (minutes)

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • User-supplied measurements and assumptions; One full hour of equal subintervals; PHF=hour count/(intervals per hour×largest interval count). Supported limits: Finite numeric values bounded to 1e9 magnitude; lists and tables contain 1–100 records unless a stricter bound is stated. Inputs use the units shown. Lists explicitly paired by a method must have matching lengths; independent polynomial coefficient vectors may differ. Respect stated physical, interpolation, policy and computational domain limits.
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Further reading

Method reference ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

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