Formula
density=flow/space-mean speed.
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Homogeneous steady flow. Use the same lane basis for flow and density; spot time-mean speed is not interchangeable.
Example Calculation
Example inputs
- Flow: 1200 vehicles/h
- Space-mean speed: 60 km/h
1200 vehicles/hour at a 60 km/h space-mean speed imply 20 vehicles/km.
Frequently asked questions
How do I use this calculator?
Enter flow, space-mean speed. The result updates automatically. Use Reset to restore the example values.
What method does it use?
density=flow/space-mean speed.. Homogeneous steady flow. Use the same lane basis for flow and density; spot time-mean speed is not interchangeable.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.