Inches Per Second to Kilometers Per Hour (in/s to km/h)

1 inch per second equals 0.09144 kilometers per hour exactly.

1 inch per second = 0.09144 kilometers per hour

How to convert inches per second to kilometers per hour

To convert inches per second to kilometers per hour, multiply the number of inches per second by 0.09144. This factor is exact. To go the other way, multiply kilometers per hour by 10.93613298 (rounded).

kilometers per hour = inches per second × 0.09144

Example: 10 inches per second = 0.9144 kilometers per hour.

About these units

Inch Per Second (in/s)

US & ImperialCurrent unit

Exactly 0.0254 m/s. Used for tape speeds.

Tape recording standardized on inch per second, often written ips. The Compact Cassette, introduced by Philips in August 1963, runs at 1 7/8 ips, which is 4.7625 cm/s, since 1.875 times 2.54 gives that figure. Open-reel machines used a ladder of speeds, each double the one below: 3 3/4 ips (9.525 cm/s), 7 1/2 ips (19.05 cm/s), 15 ips (38.1 cm/s) and 30 ips (76.2 cm/s).

Some dictation machines ran at half the cassette speed, 15/16 ips, or about 2.38 cm/s. The unit rests on the international inch of exactly 25.4 mm, so one inch per second is exactly 0.0254 m/s, and NIST lists the conversion as exact. A cassette moves at about 0.0476 m/s, which is 0.171 km/h.

1 inch per second = 0.0254 meters per second (exactly).

Sources: Wikipedia: Compact Cassette; NIST SP 811 Appendix B.8: conversion factors; Wikipedia: Orders of magnitude (speed)

Kilometer Per Hour (km/h)

Metric (SI)Current unit

The standard unit for road speeds in most countries: 1 km/h is about 0.2778 m/s.

Myriameters per hour came first, at least in French. Although the meter was defined in 1799, speeds were initially quoted using the myriameter of 10,000 meters, and the phrase myriamètres par heure appears in 1802. The Dutch adopted the kilometer in 1817 under the name mijl. English abbreviations only appeared in the late nineteenth century, and many competing forms followed, from k. p. h. in 1889 to KMPH in 1940. Reuters and The Economist still prefer kph.

SI treats km/h as a unit symbol, not an abbreviation, and it is the generally preferred form. The European Union required SI usage in 1972, and a 1975 directive requires km/h on speedometers in all languages. In the United States a 1988 NHTSA rule allowed km/h on speedometers. Exactly 3.6 km/h make 1 m/s, one mile per hour is exactly 1.609344 km/h, and one knot is exactly 1.852 km/h. Road signs and speed limits in most of the world use it.

1 kilometer per hour = 0.2777777778 meters per second (approximately).

Sources: Wikipedia: Kilometres per hour; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

See all speed units.