28 mph is approximately 24.3252 knots.
The conversion from mph to knots involves multiplying the speed value in miles per hour by the factor 0.868976, which translates the measurement into nautical miles per hour, or knots. This is useful for navigation and maritime contexts where knots are the standard unit.
Conversion Tool
Result in knots:
Conversion Formula
The formula for converting miles per hour (mph) to knots is:
knots = mph × 0.868976
This works because one nautical mile equals approximately 1.15078 statute miles. Therefore, to find how many nautical miles per hour (knots) correspond to a speed in miles per hour, you divide the mph value by 1.15078, which equals multiplying by about 0.868976.
Example Calculation:
- Given speed: 28 mph
- Multiply 28 by 0.868976: 28 × 0.868976 = 24.3253 knots
- Rounded result: 24.325 knots
Conversion Example
- Convert 15 mph to knots:
- Multiply 15 × 0.868976 = 13.03464 knots
- Result rounded: 13.0346 knots
- Convert 40 mph to knots:
- Multiply 40 × 0.868976 = 34.75904 knots
- Result rounded: 34.759 knots
- Convert 50 mph to knots:
- Multiply 50 × 0.868976 = 43.4488 knots
- Result rounded: 43.449 knots
- Convert 12.5 mph to knots:
- Multiply 12.5 × 0.868976 = 10.8622 knots
- Rounded result: 10.862 knots
Conversion Chart
The chart below shows the equivalent knots for mph values between 3.0 and 53.0. You can use this table by finding your mph value in the left column and reading across to see the corresponding knots value. This helps quick reference without calculation.
| MPH | Knots | MPH | Knots | MPH | Knots |
|---|---|---|---|---|---|
| 3.0 | 2.607 | 20.0 | 17.380 | 37.0 | 32.152 |
| 6.0 | 5.214 | 23.0 | 19.987 | 40.0 | 34.759 |
| 9.0 | 7.829 | 26.0 | 22.594 | 43.0 | 37.366 |
| 12.0 | 10.428 | 29.0 | 25.201 | 46.0 | 39.974 |
| 15.0 | 13.035 | 32.0 | 27.807 | 49.0 | 42.581 |
| 18.0 | 15.621 | 35.0 | 30.414 | 52.0 | 45.188 |
| 21.0 | 18.248 | 38.0 | 33.021 | 53.0 | 46.057 |
Related Conversion Questions
- How many knots equal 28 mph when sailing?
- What is the speed in knots for a car going 28 mph?
- Is 28 mph faster or slower than 24 knots?
- How to convert 28 mph to knots manually?
- What is the difference between 28 mph and 28 knots?
- How many knots does a plane travel at 28 mph?
- Can I use 28 mph as a speed in knots for boating?
Conversion Definitions
mph: Miles per hour (mph) is a unit measuring speed representing the number of miles traveled in one hour. It mostly used in the United States for road speed limits, vehicles speed, and other land-based speed measurements.
knots: A knot is a unit of speed equal to one nautical mile per hour, used in maritime and aviation fields. It reflects distance traveled over water or through air, consistent with geographic coordinate measurements based on Earth’s circumference.
Conversion FAQs
Why use knots instead of mph in navigation?
Knots are preferred in navigation because nautical miles correspond directly to latitude/longitude degrees, making distance and speed easier to relate on charts. Using mph would complicate position plotting since statute miles don’t align with Earth’s spherical grid.
Is the conversion factor from mph to knots exact?
The factor 0.868976 is an approximation based on the exact nautical mile definition, but minor variations exist depending on specific standards. For practical uses, this factor is accurate enough for navigation and speed conversion.
Can I convert knots back to mph?
Yes, converting knots to mph uses the inverse factor: multiply knots by about 1.15078 to get mph. This reverses the original conversion, helpful when switching units in reports or instruments.
Does wind speed in mph convert the same way to knots?
Yes, wind speed measured in mph converts to knots using the same formula. Mariners and aviators use knots for wind speeds because it aligns with nautical miles, important for consistent weather reporting.
What instruments measure speed in knots?
Marine GPS devices, airspeed indicators, and radar systems usually report speed in knots. These instruments are designed to work with nautical charts and air navigation systems, where knots are the standard unit.
