Speed converter
Miles per Hour to Knots
If you need to know how many Knots one Miles per Hour contains, the answer is 0.86897624. The conversion is linear, so 10 mph is 8.689762 kn and 100 mph is 86.897624 kn. Use the converter for any other value.
Formula 1 mph = 0.86897624 kn
Need the other direction? Knots to Miles per Hour.
How to convert Miles per Hour to Knots
Miles per hour is the standard road-speed unit in the US and UK, equal to 1.609344 km/h. One knot is one nautical mile per hour, exactly 1.852 km/h.
To convert Miles per Hour to Knots, multiply the value in mph by 0.86897624. For example, 10 mph × 0.86897624 = 8.689762 kn. This works because the ratio between the two units is constant for every value in speed.
Worked examples
| mph | kn |
|---|---|
| 1 mph | 0.86897624 kn |
| 2.5 mph | 2.172441 kn |
| 5 mph | 4.344881 kn |
| 10 mph | 8.689762 kn |
| 25 mph | 21.724406 kn |
| 50 mph | 43.448812 kn |
| 100 mph | 86.897624 kn |
Reverse conversion
| kn | mph |
|---|---|
| 1 kn | 1.150779 mph |
| 5 kn | 5.753897 mph |
| 10 kn | 11.507794 mph |
| 25 kn | 28.769486 mph |
| 50 kn | 57.538972 mph |
| 100 kn | 115.077945 mph |
When this conversion is useful
This is the calculation you need when you are reading a car spec, a weather report or an aviation document from another country. Because the factor is fixed, you can use the same number for a single measurement or for a batch: 1,000 mph is 868.976242 kn.
Is the conversion exact?
Yes for practical use: the factors come from international definitions, with rounding applied only for display.
Reference: BIPM SI Brochure and NIST SP 811. Last reviewed: 2026-11-01.
mph to kn conversion chart
The chart lists the most requested values. For a value that is not here, use the converter at the top of the page.
| Miles per Hour (mph) | Knots (kn) |
|---|---|
| 1 mph | 0.86897624 kn |
| 2 mph | 1.737952 kn |
| 3 mph | 2.606929 kn |
| 4 mph | 3.475905 kn |
| 5 mph | 4.344881 kn |
| 6 mph | 5.213857 kn |
| 7 mph | 6.082834 kn |
| 8 mph | 6.95181 kn |
| 9 mph | 7.820786 kn |
| 10 mph | 8.689762 kn |
| 11 mph | 9.558739 kn |
| 12 mph | 10.427715 kn |
| 13 mph | 11.296691 kn |
| 14 mph | 12.165667 kn |
| 15 mph | 13.034644 kn |
| 16 mph | 13.90362 kn |
| 17 mph | 14.772596 kn |
| 18 mph | 15.641572 kn |
| 19 mph | 16.510549 kn |
| 20 mph | 17.379525 kn |
| 21 mph | 18.248501 kn |
| 22 mph | 19.117477 kn |
| 23 mph | 19.986454 kn |
| 24 mph | 20.85543 kn |
| 25 mph | 21.724406 kn |
| 26 mph | 22.593382 kn |
| 27 mph | 23.462359 kn |
| 28 mph | 24.331335 kn |
| 29 mph | 25.200311 kn |
| 30 mph | 26.069287 kn |
| 31 mph | 26.938264 kn |
| 32 mph | 27.80724 kn |
| 33 mph | 28.676216 kn |
| 34 mph | 29.545192 kn |
| 35 mph | 30.414168 kn |
| 36 mph | 31.283145 kn |
| 37 mph | 32.152121 kn |
| 38 mph | 33.021097 kn |
| 39 mph | 33.890073 kn |
| 40 mph | 34.75905 kn |
| 41 mph | 35.628026 kn |
| 42 mph | 36.497002 kn |
| 43 mph | 37.365978 kn |
| 44 mph | 38.234955 kn |
| 45 mph | 39.103931 kn |
| 46 mph | 39.972907 kn |
| 47 mph | 40.841883 kn |
| 48 mph | 41.71086 kn |
| 49 mph | 42.579836 kn |
| 50 mph | 43.448812 kn |
| 60 mph | 52.138575 kn |
| 70 mph | 60.828337 kn |
| 80 mph | 69.518099 kn |
| 90 mph | 78.207862 kn |
| 100 mph | 86.897624 kn |
Frequently asked questions
How many Knots are in 1 Miles per Hour?
1 mph equals 0.86897624 kn.
How do I convert Miles per Hour to Knots?
Multiply the mph value by 0.86897624. Example: 25 mph = 21.724406 kn.
What is 2.5 mph in kn?
2.5 mph = 2.172441 kn.
Is the mph to kn conversion exact?
Yes for practical use: the factors come from international definitions, with rounding applied only for display.
Does the calculator work offline?
Yes. The conversion runs in your browser with JavaScript, so it works after the page has loaded, even without a connection.