Car Journey Buffer Calculator

For a car journey, add a chosen time buffer to a base duration using your entered values.

How to use Car Journey Buffer Calculator

1. Enter Base Journey Time, Buffer. 2. Use the total road distance and an assumed overall average speed. Traffic, stops, road routing and speed limits are not retrieved. The buffer is chosen by you and may be zero. It is added once and is not a reliability guarantee. 3. Select Calculate or press Enter. 4. Select Copy result to copy the answer, or Reset to clear the form and result.

Why use this tool?

Compare car journey planning assumptions on one consistent distance and time basis.

How the calculation works

Buffered duration = base duration + entered buffer. Use the total road distance and an assumed overall average speed. Traffic, stops, road routing and speed limits are not retrieved. The buffer is chosen by you and may be zero. It is added once and is not a reliability guarantee. Durations round to the nearest second; other quantities round to at most six decimals (percentages to two). Nonzero subprecision values are identified.

Example

Worked example: Base Journey Time = "2 h 20 min"; Buffer = "40 min". Result: 3 h 0 min.

Practical tip

Include breaks or transfer waits either in the base or the buffer, so they are counted once.