Inches, Feet, Meters, Oh My: Why America Still Won't Go Metric

Only Three Countries Don't Use Metric

The United States, Myanmar, and Liberia. That's it. Every other country on Earth has officially adopted the metric system. So what happened?

The answer involves pirates, Congress, and a surprisingly expensive road sign.

A Brief History of Measurement Chaos

Before Standardization

In medieval Europe, measurements were a disaster:

• A "foot" was literally based on the king's foot (it changed with each king)


• A "yard" was the distance from the king's nose to his outstretched thumb


• An "acre" was the amount of land a team of oxen could plow in one day


• A "mile" came from the Roman "mille passus" (1,000 paces)

Every town had slightly different measurements. Trade was a nightmare.

The French Solution (1799)

France created the metric system based on nature:


• Meter: 1/10,000,000 of the distance from the equator to the North Pole


• Gram: Weight of 1 cubic centimeter of water


• Liter: 1,000 cubic centimeters

Everything scales by powers of 10. Simple. Elegant. Logical.

America Almost Went Metric (Twice)

Attempt 1: The 1790s

Thomas Jefferson proposed a decimal measurement system for the new nation. Congress was interested but delayed. Meanwhile, France sent scientist Joseph Dombey to America with official metric standards (a copper kilogram and a meter rod).

His ship was blown off course to the Caribbean, where he was captured by pirates. He died in captivity. The metric standards never arrived.

Some historians call this the reason America isn't metric today.

Attempt 2: The 1970s

In 1975, Congress passed the Metric Conversion Act, establishing a voluntary transition to metric. President Gerald Ford signed it. The US Metric Board was created.

The key word: voluntary.

Without mandatory requirements, industries that would bear the conversion cost lobbied against it. Public interest faded. President Reagan disbanded the US Metric Board in 1982.

Why It's So Hard to Switch

The Cost Problem

Converting isn't just about learning new numbers. It requires:

Infrastructure changes:


• Every road sign in America (replacing or adding metric)


• Manufacturing equipment retooled for metric


• Building codes rewritten


• Plumbing and construction materials restandardized

Estimated cost: Various studies have put a full US conversion at hundreds of billions of dollars.

Road signs alone:


• The US has approximately 30 million road signs


• Replacing or supplementing each one costs hundreds of dollars


• Total: billions just for road signs

The Human Factor

People resist change, especially in daily life:

• "I know what 72 degrees feels like. What's 22 Celsius?"


• Recipes passed down for generations use cups and teaspoons


• Football fields are 100 yards, not 91.44 meters


• "I'm 5 foot 10" is deeply ingrained in identity

The Industry Pushback

Key industries opposed conversion:

Construction:


• Lumber is standardized to imperial (2x4, 4x8 sheets)


• Every blueprint, code, and regulation would need rewriting


• Workers retrained

Manufacturing:


• Retooling factories is enormously expensive


• Existing inventory becomes incompatible


• Supply chains disrupted during transition

America Is More Metric Than You Think

Despite the perception, the US actually uses metric extensively:

Science and Medicine: All scientific research uses metric. Medications are dosed in milligrams and milliliters, and lab work is done entirely in metric units.

Military: NATO standardization requires metric. Maps use kilometers, and ammunition is measured in millimeters (5.56mm, 9mm).

Trade and Manufacturing: Car engines are measured in liters (2.0L, 3.5L). Nutrition labels show grams. Photography uses millimeters (50mm lens). Electronics use metric (3.5mm jack).

Food and Drink: Wine and spirits come in milliliters and liters (750mL bottle). Soda is sold in liters (2-liter bottle). Nutrition facts are listed in grams.

Sports: Track and field uses 100 meters, 5K, 10K, and marathon (42.195 km). Swimming pools are 50m. All Olympic events are metric.

The Dual System Problem

Living with both systems causes real issues:

The Mars Climate Orbiter ($327 Million Mistake)

In 1999, NASA lost the Mars Climate Orbiter because one engineering team used imperial units and another used metric. The spacecraft received thrust calculations in pound-force instead of newtons.

It entered the Mars atmosphere at the wrong angle and was destroyed. Cost: $327.6 million.

Medical Errors

Unit confusion between metric and imperial has contributed to medication dosing errors. A dose meant in milligrams interpreted as another unit can be dangerous.

Trade Complications

US manufacturers often maintain two product lines - imperial for domestic and metric for export. This adds cost and complexity.

Countries That Successfully Switched

United Kingdom

Officially metric since 1965, but still uses miles for road distances. People use stone for body weight and pints for beer. It shows that switching is gradual and messy.

Canada

Switched in the 1970s. Weather is in Celsius and distances in kilometers, but people still use feet and inches for height. Close to full adoption after 50 years.

Australia

Switched in 1970, completed by the mid-1980s. Full adoption in daily life. Considered one of the most successful transitions worldwide.

Common factor: Government-mandated transitions with set deadlines work. Voluntary ones don't.

The Gen Z Metric Shift

Younger Americans are increasingly metric-comfortable. School science is taught exclusively in metric. International online communities use metric. Global content on YouTube and social media is metric. Gaming and tech industries use metric. And travel to metric countries exposes them to it firsthand.

Some predict a gradual, organic shift rather than a mandated one.

Quick Conversion Reference

Convert Any Measurement Instantly

Tired of doing the mental math? Use our unit converter to convert between metric and imperial instantly. Supports length, weight, volume, temperature, and dozens of other unit types.

Disclaimer

This article is for informational and educational purposes only. Historical facts and conversion figures are presented to the best of our knowledge and may be subject to interpretation. Convertz.app provides conversion tools only.