Knots to kilometers per hour (kn to km/h) converter

What is a knots to kilometers per hour converter?

A knots to kilometers per hour converter is an online tool that translates a speed expressed in knots (kn) into the equivalent value in kilometers per hour (km/h), and the other way around. The knot is the standard unit of speed in marine navigation and aviation, while kilometers per hour is the everyday metric unit used on land in most of the world. Because charts, weather reports, and instruments may use either unit, having a quick way to move between them is helpful for sailors, pilots, students, and anyone reading a wind or vessel speed.

One knot is defined as one nautical mile per hour. Since a nautical mile equals exactly 1,852 meters, one knot equals exactly 1.852 kilometers per hour. This makes the conversion clean and easy to verify.

How it works

The conversion relies on a single fixed factor. To go from knots to kilometers per hour, you multiply by 1.852. To go the other way, from kilometers per hour to knots, you divide by 1.852 (or, equivalently, multiply by about 0.539957).

The converter above lets you type a value into either field. Enter a speed in knots and it shows the matching kilometers-per-hour value; enter a speed in kilometers per hour and it returns the value in knots. Both fields also let you switch to related speed units such as miles per hour (mi/h) and feet per second (ft/s) if you need them.

Formula

The relationship between the two units is exact:

$v_{km/h} = v_{kn} \times 1.852$

To reverse the conversion, divide by the same factor:

$v_{kn} = \frac{v_{km/h}}{1.852}$

Knots to kilometers per hour conversion table

The table below lists common speeds in knots and their exact equivalents in kilometers per hour.

Examples

Example 1: One knot

The simplest case shows the factor directly. Converting a single knot:

$1 \text{ kn} \times 1.852 = 1.852 \text{ km/h}$

So 1 knot is exactly 1.852 kilometers per hour.

Example 2: A cruising sailboat at 10 knots

A sailboat moving at 10 knots is making good progress. To express that on a metric speedometer:

$10 \text{ kn} \times 1.852 = 18.52 \text{ km/h}$

Ten knots equals 18.52 kilometers per hour.

Example 3: A fast vessel at 100 knots

For a high-speed craft or a strong wind reading of 100 knots:

$100 \text{ kn} \times 1.852 = 185.2 \text{ km/h}$

One hundred knots equals 185.2 kilometers per hour.

Example 4: Back to knots

If a speed of 1.852 km/h is reported and you want it in knots, divide by the factor:

$\frac{1.852 \text{ km/h}}{1.852} = 1 \text{ kn}$

This confirms that 1.852 kilometers per hour is exactly 1 knot.

Notes

• The factor 1.852 is exact, not rounded, because a nautical mile is defined as exactly 1,852 meters.
• Do not confuse the knot with the nautical mile: a knot is a speed (distance per hour), while a nautical mile is a distance.
• Saying “knots per hour” is incorrect; a knot already includes the per-hour part.
• Weather services often report wind speed in knots, so converting to km/h can make forecasts easier to picture on land.

Frequently asked questions

How many km/h are in one knot?

One knot equals exactly 1.852 kilometers per hour, because a nautical mile is defined as 1,852 meters.

How do I convert knots to km/h in my head?

Multiply the knot value by 1.852. For a quick estimate, multiply by roughly 1.85, or simply double the number and subtract a little.

How do I convert km/h back to knots?

Divide the kilometers-per-hour value by 1.852, which is the same as multiplying by about 0.54.

Why do ships and aircraft use knots instead of km/h?

Knots tie directly to nautical miles, which relate to degrees of latitude on a chart. This makes navigation and plotting positions more convenient at sea and in the air.

Is the 1.852 factor exact or approximate?

It is exact. The international nautical mile was standardized at precisely 1,852 meters, so one knot is precisely 1.852 km/h.

What is 20 knots in kilometers per hour?

Twenty knots equals 37.04 km/h, found by multiplying 20 by 1.852.