Roman Paces to Millimeters (passus to mm)

1 Roman pace equals 1,480 millimeters exactly.

1 Roman pace = 1,480 millimeters

How to convert Roman paces to millimeters

To convert Roman paces to millimeters, multiply the number of Roman paces by 1,480. This factor is exact. To go the other way, multiply millimeters by 0.0006756756757 (rounded).

millimeters = Roman paces × 1,480

Example: 10 Roman paces = 14,800 millimeters.

Approximate value. Standards for the Roman pace varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.

About these units

Roman Pace (passus)

Ancient RomanHistorical unit (no longer in standard use)Approximate value

Five Roman feet, about 1.48 m. A passus was a full stride, from the lift of one foot to the same foot landing again.

Counting a pace by both feet is the key to the Roman passus. Unlike a single step, it ran from the point where one heel leaves the ground to where that same heel lands again, so it covered two steps, each called a gradus. Marcus Vipsanius Agrippa is credited with fixing it at five Roman feet, which comes to about 1.48 m, the figure used here. The exact size depends on the foot, whose surviving measures vary by a few millimeters.

A thousand paces, mille passus, formed the Roman mile of about 1.48 km, and the English word mile descends from that phrase. Milestones along roads such as the Appian Way marked distances in this unit,. The pace also sat in a chain of units: ten feet made a decempeda, and 120 feet made an actus. In imperial terms the passus is a little under five feet.

1 Roman pace = 1.48 meters (approximately).

Sources: Wikipedia: Pace (unit); Wikipedia: Ancient Roman units of measurement

Millimeter (mm)

Metric (SI)Current unit

One thousandth of a meter. Used in engineering, manufacturing and rainfall measurement.

Carl Friedrich Gauss put the millimeter at the base of his 1832 proposal for absolute units, pairing it with the milligram and the second, although the centimeter-based CGS system later won out among scientists. The name combines the metric prefix milli-, from the Latin for one thousand, with the meter. Since 1983 a millimeter has been tied to the speed of light: it is the distance light covers in 1/299,792,458,000 of a second.

Millimeters are the language of fine mechanical work. Standard rulers are divided into them, digital calipers commonly read to 0.01 mm, and mechanical pencil leads come in 0.5 and 0.7 mm. Copy paper is about 0.1 mm thick, and a thin hair, at 0.02 to 0.04 mm across, is close to the smallest thing the naked eye can see. A wave with a frequency of 300 GHz has a wavelength of 1 mm. An inch is exactly 25.4 mm. One trap for readers in the United States is that mil there traditionally means a thousandth of an inch, not a millimeter.

1 millimeter = 0.001 meters (exactly).

Sources: Wikipedia: Millimetre; Wikipedia: Centimetre-gram-second system of units; NIST Guide to the SI, Appendix B.8: conversion factors

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