Miles per Hour to Feet per Second Converter | mph to ft/s

What this converter does

Miles per hour tells you how fast you are travelling, but it hides a more immediate question: how much ground are you covering each second? Feet per second answers that, and this converter makes the switch. Enter a speed in mph and it gives you ft/s, the distance crossed every second. Type the value and read off the result.

The conversion factor

One mile per hour is 1.46667 feet per second, so:

ft/s = mph × 1.46667

It falls out of the units: a mile is 5,280 feet and an hour is 3,600 seconds, and 5,280 divided by 3,600 is 1.46667. The ft/s figure comes out larger than the mph, since each hour of travel is packed into far fewer seconds.

Feet covered every second

This conversion turns an abstract speed into a distance you can picture. The anchor to hold is that 60 mph is exactly 88 ft/s, because one mile a minute is 5,280 feet over 60 seconds. So at 60 mph you cross 88 feet, the better part of a basketball court, every second. That framing is what makes the conversion genuinely useful: it shows how little time you have to react, since the faster you go, the more ground slips by before you can even lift your foot.

A worked example

Say you are driving at 60 mph and want to know how far you travel during a reaction time of about a second and a half.

• 60 × 1.46667 = 88 ft/s
• 88 × 1.5 = 132 feet

So at 60 mph you cover 88 feet every second, and in the second and a half it takes to notice a hazard and react, you have already travelled 132 feet before the brakes even start to bite. Seeing it in feet per second makes the case for leaving room far better than the mph figure alone.

Common mph speeds in ft/s

Notice 30 mph is exactly 44 ft/s and 60 mph is exactly 88 ft/s, the half and the whole of that mile-a-minute anchor.

Where it is useful

The standout use is road safety, where stopping and reaction distances are worked from how many feet a second a vehicle covers, so a speed in mph has to become ft/s first. Driver training leans on it for the same reason, to show how distance grows with speed. Physics problems in feet want speeds in ft/s to keep the working consistent. And anyone curious about how much ground a given mph really eats each second can see it here. It is the conversion that turns travel speed into the distance behind it.

Questions people ask

How do I convert mph to ft/s?

Multiply the speed in mph by 1.46667. A useful anchor is that 60 mph is exactly 88 ft/s.

What is 60 mph in ft/s?

Exactly 88 ft/s, which is one mile every minute, or 88 feet every second.

Why is the ft/s number bigger than the mph?

An hour holds 3,600 seconds, so the distance you would cover in an hour is squeezed into each second as a larger-looking figure in feet per second.

References

1. National Institute of Standards and Technology (NIST), Special Publication 811, Guide for the Use of the International System of Units (unit conversion factors). https://www.nist.gov/pml/special-publication-811