How many knots is 1 mph?

1 mph equals 0.868976 knots. Equivalently, 1 knot equals 1.15078 mph. The relationship comes from the definitions of the nautical mile (1,852 m) and the international mile (1,609.344 m).

Why do aviation and maritime navigation use knots?

Knots are tied directly to nautical miles, which correspond to arc-minutes of latitude. This makes great-circle navigation on spherical charts simpler than using land-based units like mph or km/h.

What is the Beaufort scale?

The Beaufort scale is a 0–12 empirical wind-force scale developed by Admiral Francis Beaufort in 1805. Each level corresponds to a range of wind speeds in knots and has observable effects on land or sea, from calm (Beaufort 0) to hurricane force (Beaufort 12, ≥64 kt / ≥74 mph).

How fast is a typical commercial aircraft in mph and knots?

A commercial jet cruises at roughly 500–575 mph (435–500 knots) at altitude. At sea level the speed of sound is about 761 mph (661 knots); aircraft cruise below Mach 1.

Is this converter accurate?

Yes. The tool uses the exact factor 0.868976 knots per mph (derived from the international mile and nautical mile definitions) and rounds results to four decimal places.

Miles per Hour to Knots Converter

Name: Miles per Hour to Knots Converter
Availability: InStock
Author: Nham Vu

Convert mph to knots or knots to mph instantly. Includes a Beaufort wind scale and common speed reference table.

Speed Converter

Miles per Hour (mph)

Knots (kt)

Conversion Formula

knots = mph × 0.868976

mph = knots × 1.15078

One nautical mile = 1,852 m; one international mile = 1,609.344 m. Dividing gives the exact factor.

Reference Table — Common Speeds & Beaufort Scale

Click any row to load it into the converter.

Description	mph	Knots (kt)

Summary

Convert mph to knots or knots to mph instantly. Includes a Beaufort wind scale and common speed reference table.

How it works

Enter a speed value in the mph field or the knots field.
The converter applies the exact factor: 1 mph = 0.868976 knots.
The opposite field updates automatically in real time.
Use the Swap button to reverse the direction of conversion.
Click any row in the reference table to load that value into the converter.

Use cases

Pilots converting airspeed from mph to the knots used in aviation.
Sailors checking wind speed forecasts given in mph against nautical charts.
Weather observers mapping Beaufort scale wind ranges to mph.
Students preparing for maritime or aviation exams.
Navigation software developers needing a quick sanity check.
Travelers comparing vehicle speeds in countries using different units.

Frequently Asked Questions

Last updated: 2026-07-23 · Reviewed by Nham Vu