Trip Generation Rate Calculator

Work out trip generation rate instantly with clear inputs, formula shown and shareable results.

About Trip Generation Rate Calculator

Trip generation multiplies development size by a published trip rate per unit, then extracts the peak hour as a percentage of the daily total, typically ten to fifteen percent. The directional split matters because an intersection is sized on the heavier direction: residential areas are outbound dominated in the morning and inbound in the evening.

Formulas

Daily trips

Trips = development units x daily trip rate per unit

Peak hour

Peak trips = daily trips x peak hour share, split by direction

Worked example

With the default values below, Trip Generation Rate Calculator returns Daily two way trips of 1,200. Change any input above and every figure here is recalculated in your browser.

Inputs used

Development sizeminimum 1 units: 200 units
Daily trip rate per unitminimum 0.01 trips/unit: 6 trips/unit
Peak hour share of daily tripsaccepts 1–40 %: 12 %
Inbound share in the peak houraccepts 0–100 %: 60 %

Results

Daily two way trips: 1,200 trips
Peak hour trips: 144.0 trips
Peak hour inbound trips: 86.4 trips
Peak hour outbound trips: 57.6 trips

Step by step

1Values used
2Daily trips
3Peak hour
4Daily two way trips= 1,200 trips
5Peak hour trips= 144.0 trips
6Peak hour inbound trips= 86.4 trips
7Peak hour outbound trips= 57.6 trips

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is the Trip Generation Rate figure worked out?

Trips = development units x daily trip rate per unit. Trip generation multiplies development size by a published trip rate per unit, then extracts the peak hour as a percentage of the daily total, typically ten to fifteen percent.

Where do trip rates come from?

Surveys of comparable existing developments, published in trip generation manuals by land use category. Local rates should be preferred where available because mode share differs sharply between places.

What values do I need to enter?

This calculator takes 4 inputs: Development size, Daily trip rate per unit, Peak hour share of daily trips, Inbound share in the peak hour. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.