Speed Converter

Enter a speed, choose the unit it is in and the unit you want.

Updated October 27, 2026

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<iframe src="/embed/en/unit-converters/speed-converter/" width="480" height="640" title="Speed Converter" loading="lazy" style="border:0;max-width:100%"></iframe>
<script>window.addEventListener('message',function(event){if(event.origin!==''||!event.data||event.data.type!=='calc-embed-height')return;var f=document.getElementsByTagName('iframe');for(var i=0;i<f.length;i++){if(f[i].contentWindow===event.source){f[i].style.height=event.data.height+'px';}}});</script>

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Formula

result = value × (metres per second in the from unit) ÷ (metres per second in the to unit)

Every unit is stored as a fixed multiple of the base unit (m/s), so any pair converts in one step.

Worked example

100 km/h to mph: 100 km/h = 100 × 1000 ÷ 3600 = 27.7778 m/s, and 1 mph = 0.44704 m/s, so 27.7778 ÷ 0.44704 = 62.137119 mph.

Quick reference

1 mph = 0.44704 m/s (exactly), 1 km/h = 0.277778 m/s, 1 knot = 0.514444 m/s, 1 ft/s = 0.3048 m/s (exactly).

Frequently asked questions

How do I convert km/h to mph?

Divide the speed in km/h by 1.609344. For example 100 km/h is 100 ÷ 1.609344 = 62.137 mph.

How many km/h is 1 m/s?

Exactly 3.6 km/h, because there are 3,600 seconds in an hour and 1,000 metres in a kilometre. So 10 m/s is 36 km/h.

What is a knot in km/h?

A knot is one nautical mile per hour, and a nautical mile is exactly 1,852 metres, so 1 knot is 1.852 km/h. 50 knots is 92.6 km/h.

How many mph is 100 km/h?

100 km/h is about 62.137 mph. As a rule of thumb, multiply km/h by 0.62.

How we calculate

Speed Converter

Formula

Worked example

Quick reference

Frequently asked questions

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