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# Why does the US Have a Different Measurement System?

Tricia Christensen
Tricia Christensen

The US measurement system is a confusing matter and still holds itself apart from the metric system employed by most other countries. There are a few exceptions. Medical and scientific fields use the metric system, and many items for trade are now measured in the International System of Units (SI), also called the metric system.

The US measurement system is based on the English system, or imperial units, though England has now long since converted to SI. However, the change to SI was not an easy passage in the mid 19th century. Though Britain is officially on the metric system, imperial units are still widely used.

Legally, according to laws passed in 1988, SI became the standard measurement system for trade and commerce in the US. SI is also taught in schools at a relatively young age, but it is difficult to make the conversions.

If one initially learns the metric system, it is far easier. Everything is constructed on a base ten approach, so conversion from centimeters to meters is a simple matter. Conversely, the US measurement system is often problematic. It is not consistent in its measurements so conversion is quite challenging.

For example, twelve inches equal a foot, but eight (liquid) ounces equal a cup. Sixteen (weight) ounces equal a pound, but three feet equal a yard. Children must memorize quite a bit to perform appropriate conversions.

Since children usually first learn to measure by inches, the metric system cannot be properly taught until multiplication skills are mastered. An inch converts to 2.54 centimeters, thus anything above ten inches involves two-digit multiplication. This is a skill not mastered by most students until the later part of third or even fourth grade.

If, conversely, the metric measurement system were adopted immediately, children would probably learn it just as quickly as they learn the US system. However, since real-life examples are often included in teaching, this would be difficult to do. If one buys a TV, he or she buys a 20-inch screen, not a 50.8-cm screen. If one purchases milk, the choice is a quart, a pint or a gallon, not a measurement in liters (L) or milliliters (mL).

In general, consumer products still adhere to the US measurement system, as well as American cookbooks, so these figures must be known. Essentially, this means US children must learn two measurement systems, and unless they plan to export items, or become doctors or scientists, they may never fully master SI.

Unless the US government insists on the conversion in products, and teaching in the metric system, it is likely that the US will retain their own measurement system. However, with increasing globalization it makes sense to consider that much of the world, and especially the scientific world, relies on the metric system. Our ability to learn it makes us have that much more in common with our fellow countries.

Tricia Christensen

Tricia has a Literature degree from Sonoma State University and has been a frequent AllTheScience contributor for many years. She is especially passionate about reading and writing, although her other interests include medicine, art, film, history, politics, ethics, and religion. Tricia lives in Northern California and is currently working on her first novel.

Tricia Christensen

Tricia has a Literature degree from Sonoma State University and has been a frequent AllTheScience contributor for many years. She is especially passionate about reading and writing, although her other interests include medicine, art, film, history, politics, ethics, and religion. Tricia lives in Northern California and is currently working on her first novel.

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anon993702

Americans need to wise up, period. The metric system is so much easier to use, and more precise. The problem is they compare the current English system to the metric - which will always make it confusing. Just make the jump and go metric. Signed.

An embarrassed American

anon968108

I can't understand how American people who historically set themselves free by kicking out the English and all kinds of English rules, taxes, use an English measurement system every day.

For example, French people replace king taxes by.... it's not a good example (I'm french) and we have many more taxes today than when our kings were alive.

But, if your American identity is set by the use of imperial measurement, use it and who else can say his system is better than yours? I've never gone to the United States of America, but if I travel there, I'd probably be happy to use, for the time of the trip, your imperial measurement system. In every country where I travelled, I used a calculator for currency conversion anyway, so why not use one to convert kilos to pounds, liters to ounces and many more incredible measures which probably makes me the hugest brain storming of my life.

So, be Americans, be free, be imperial if you want! Also don't let the whole world say the International Standards of measurement are better than your system.

PS: Imagine an American football championship, not in yards, but in meters! American people are so different from the entire world, we must preserve and protect them, like any rare or endangered animal so let them use their impossible system.

anon959247

First of all, it's not the "metric system", it's the "SI system". It's not only "inches" and "yards"; it's also "pounds per square inches", etc. which are extremely simple to express in SI-units.

As a matter of fact, all US units are based on the SI-system, but still school children (and engineers) are forced to do meaningless calculations (with high risk of error), for stupid political reasons (to adapt to the laziness and xenophobia of less educated people). I have never met an American scientist who supports the US measurement system.

The cost of the transition is only a pretext, and if done gradually, they are negligible compared to the profits of exporters and the avoidance of useless calculations.

By the way, "natural units?" That is simply not true. How long is your thumb, or your foot? How "natural" is a pound or a gallon?

anon360264

The British Imperial Standard system of measurements, like the American Standard system (which has some variations from the British system as with U.S. (fluid) ounces), were suited to their time.

Last century, in Australia, when I was younger, the conversion from Imperial to Metric took place and this removed the need to memorize at school the 'how many feet in a mile?' types of nformation required for a good education. I did not like initially the Metric system as the kilometer was shorter than the mile and I thought the new system should be bigger and better, but one matures.

As the Metric system became ingrained, I noted my reaction in the company of Americans when in Japan when we spoke about lengths. As I have found, in a foreign country, everything is out of context until you determine how to relate it to your experience.

In our conversation, the Americans answered a question I asked about the size of a gap by saying "inch". I said, "What was that?". The answer again was "inch". I was expecting to hear so many centimetres or millimetres or a meter. Then when I asked the Americans what they were talking about, as I thought that this was a word common only in the U.S. They showed the length between thumb and forefinger describing it as 2.5cm.

At that point, it struck me. I was half embarrassed I did not recognize what they were talking about. I liked the "inch" as it was a good, easy-to-use length. But, I also recalled my visceral reaction: the use of "inch" was such an anachronism. While for a brief moment I felt the nostalgia of the late '60's and early '70's as a character amidst those of an episode of Flipper, it struck me how Americans were rooted in something so old.

I encouraged my American colleagues to metricate and catch up with the modern world. I am sure that while my colleagues agreed with me, as Americans often do, they would not be the ones to set about trying to metricate America. Why? Americans do as Americans do and will not change. That is much like how they cling onto their infamous "Second Amendment": the right to bear arms. That is another anachronism that no one in U.S. government has the guts to try and change, despite the mass murder of school kids in America by Americans brandishing the right to bear arms.

The flaws in the American model are quickly apparent. As the world changes, Americans too will change and upgrade and improve their system. Just do not hold your breath waiting. Meanwhile, I still have nostalgia for the "inch" and wish the Metric system had something like it rather than "2.5cm"! By the way, when I visited the U.S, with all the different measurements, it felt like I was in an episode of Doctor Who. The Imperial System evokes childhood memories and sentiments. The Metric system is for adults.

anon344617

I find myself back on this site searching how many Mbps is my company supplying me. The first time was when I was searching on a 4.3" screen ZTE Warp how to pick the best laptop by myself. I started to notice that the laptops I was searching for seemed to have something that what important and that was the processing speed rating.

I'm talking about, for example, my AMD A6 runs at 4400M. So I ended up with a HP Pavilion g6 15.5". Have had it since Christmas my gift to myself and I am happy most of the time. I wish I could remember the password and username I registered under. However I'll post it anonymously anyway. --Tom

anon325427

I was born and raised in Russia, and never even heard of the imperial system until I turned 15 or something. I'm going to US this year for a few months so I'm learning measurements. When you've lived for 20 years dividing and multiplying by 10, it's sure as hell difficult to convert. You can only memorize until it becomes automatic.

anon316212

Metric measure is probably less used in America today than it was 15 or 20 years ago. It is not used at all in everyday life. Even the beginnings of metric measure that crept in during the 70s and 80s have receded.

anon306983

Pres. Reagan and Prime Minister Thatcher brought down the Belin Wall and the Soviet Union. How? They practised and preached freedom and the free market.

Both of them literally stopped "metrication" because people were demanding compulsion and exclusivity. America has legalized metric units since 1866.

Anyone or any organization that wants to go metric is free to do so.

No metricated country ever sent anyone to the moon, so stop demanding America drop down to your simple lower level.

anon285890

We would have been better off with the metric system. I passed that course with flying colors, but when it came to American math, it was confusing and, hard to remember and I did not do well in it, to say the least.

anon269664

I learned imperial as a child. Then we (NZ) brought in metric decades ago. 5280 feet in a mile seems ridiculous in comparison. I am a furniture maker who daily gives thanks for that wondrous measurement the millimeter. Dealing with fractions of an inch is so last century. --Pete

anon261666

Why doesn't everyone switch to Kelvins? It seems more logical to me. It is not possible for anything to be cold; it can only have less heat or energy, therefore it would make sense for zero to be the complete absence of heat. Most countries on the metric system still use centigrade for a majority, if not all, of their temperature measurements, yet Kelvin is the base unit for the SI.

anon241952

Exactly. I have lived here for about 18 years and this imperial system still gets me. It's a pain to use. Key values for temperatures and other common phenomena are taken pretty much sucked from the thumb.

anon187551

I'm a Canadian, and I grew up learning the metric system, and the imperial system. My school curriculum had an entire unit on just conversions and the like (but only with lengths, not with liquids or weight). Honestly the imperial system makes no bloody sense to me. I usually use metric so i don't understand the majority of the imperial system. I'm all right with inches, feet and yards, but ounces, gallons, pints? No clue about what any of those are, and what their metric equivalents would be.

I understand that there would be some problems with the US switching to metric, but the metric systems makes so much more sense. The whole thing is based on 10's, and honestly a child could learn it at age 6 (I did), it's so much easier than the imperial system.

Hopefully America will see the light someday, but to be fair they have much bigger problems than switching to the metric system right now.

anon177768

Right back at you amypollick. Peace.

amypollick

@anon177464: Of course I didn't think America was the only country giving aid and assistance to Japan. I'm not quite that ignorant. Or arrogant. I was simply speaking for my country, since I live here. And re-reading my comment, I don't quite see how you construed what I said to mean that I felt our aid to Japan was the only aid they received. I think the point I was trying to make is that, for all our faults, we really do try to help other people. And I can tell you those of us who had friends and loved ones lose everything in the April tornadoes appreciate everything anyone has done for us. The Japanese government sent 8,000 blankets and plastic tarps to us. I and many others were extremely humbled by this generosity, considering what they've been through. It was a beautiful thing to do and we truly appreciate it.

Hey, as long as your Prime Minister is doing a good job for your country, more power to her. I hope she has a successful administration.

If I misunderstood you, I do apologize. If I offended you in any way, I also apologize. Be well and be blessed.

anon177464

Sorry amypollick, I didn't really mean to offend. Just feeling tired and cranky and working night shift. I just don't like the imperial system or blind faith. Australia is 4,078 across and we don't have any Disney parks! That's why my family visited one of yours last year (even though you're so far away!). We found virtually everyone we met to be friendly and helpful. Not one person thought we were from Austria (one lady did ask if we were from France though!?). I don't dismiss anyone as a human being for believing in a God or for any other reason. Just a little misguided.

It is good that the U.S is assisting in the Japan disaster, just as I'm sure they assisted in our recent floods and the New Zealand earthquakes. Just as we will aid the U.S with their recent storms. Australia donated several million dollars and thousands of emergency workers for hurricane Katrina. Our government footed the bill and hasn't asked for any of it back. Helping other countries is not unique to the U.S. Australia and most first world countries are assisting Japan.

Our prime minister visited Japan very shortly after the tsunami struck to offer moral as well as financial support; and no, Australia didn't cause it either, but unlike you I do think we are "obliged to help these people." And I don't suppose the other 45+ countries helping will be asking for "a dime in repayment" either. Did you really think only America was helping in Japan? Now that's what I call arrogance.

For some reason I feel the need to mention that our Prime Minister is a female atheist, not born in this country who lives in sin with her boyfriend. I don't like jingoism either but I must say that warms my heart.

Re-reading what I wrote before I think I was trying to be complimentary to America in that it's quirky and different and should stay that way.

amypollick

@anon164176: And you are the victim of some rather nasty propaganda. You can, indeed, buy guns at sporting goods retailers and places like Wal-Mart. If you have a legal permit, issued by the local law enforcement authorities, you can buy handguns there. You cannot buy semi-automatic weapons. And you cannot buy any guns in any supermarkets.

I've never been to a Disney park, but since the U.S. measures 3,000 miles, excuse me, 4,828 kilometers, from shore to shore, it makes sense that there should be a Disney park on each coast. Unless I'm mistaken, there are also Disney parks in Tokyo, Paris, Hong Kong and Shanghai, all cities where the metric system is the standard system of measurement.

I am not jingoistic enough to spout that my country has no problems, no issues, and is without parallel in the world. The U.S. has plenty of problems, and so does every country on this round world.

And Americans are to be dismissed as human beings simply because many of us have faith in God? That is the absolute pinnacle of arrogance. The U.S. is a diverse nation of 300 million people and most of us are reasonably happy here. People clamor to get in here, not to get out. And if anyone wants out, they are free to emigrate to any country where they will be welcomed.

Yes, we have problems. We stick our noses where they have no business being. And right now, we have ships from our Navy off the coast of Japan, ferrying food, bottled water, supplies and loaning the expertise of our Seabees and sailors to help people whose country has been devastated by a natural disaster. We didn't cause it, and we are in no way obligated to assist these people. We do it because we care about the welfare of others besides ourselves. And our government will foot the bill. We'll never ask Japan for a dime in repayment.

If that and using the imperial measurement system makes us somehow sub-human, inferior and lower on the evolutionary ladder than enlightened persons who turn up their noses at us for our backward beliefs, then that's all right.

anon164176

Which makes more sense?

1" of rain falling on 1 square foot of roof catches 0.623 gallons of rainwater. or:

1mm of rain on 1 square meter of roof = 1 liter of water.

An average man's stride is 1 meter so it's very easy to get an approximate measurement by pacing out.

You average about 100 kmh on highways so if your destination is 250 kms away it's an easy calculation. At 70 mph how long away is 250 miles?

Water freezes at 0 and boils at 100 not 32 and 212.

1 liter of water = 1 kg. 1 gallon of water = 8.35 lbs. The imperial system is outdated and pretty much makes no sense. That's why the US should keep it.

In the US you can buy guns in the supermarket, around half the population believes in creationism, there is a choice of Disneylands, food servings are at least twice what you need, almost everyone believes in God and they have the imperial system.

All these things add up to an interesting and quaint place to visit - you just wouldn't want to live there.

anon152563

As an American and a well-traveled global citizen, I can personally say that, in the absence of tools, the Imperial System is much more useful than Metric.

When guessing the length of an object, one can compare the length with a corresponding body part, using a short pace as a foot (measurement). It is easier to walk an intersection and accurately guess the length in feet than in meters.

Finally, Americans don't use the Imperial System because they "think it is American." Any American who paid attention in third grade history should know that the Imperial System is British in origin (America isn't an imperial nation). The reason American still uses the Imperial System is because the majority of America is rural, and in the rural world, the Imperial System is much more practical.

anon150037

Re: next town in time reference.

Although I can understand your desire to know distance verses time, distance can be rendered to a more arbitrary state, depending on where the person lives. When I had lived in the countryside, distance was preferable, due to the fact that miles could be thought of as 50-90 seconds. That said, time was a constant and distance was the variable, when it came to travel.

However, if a person resides in a larger urban center (e.g., Chicago, New York, Paris, etc) then a distance of five miles or kilometers almost can be rendered arbitrary.

In the country, I could expect to arrive within 5-8 minutes with that distance. In the city, it could take me 5-40 minutes to cover the same distance. A time measurement is taking into account traffic, time of day, and location. So, it is actually more functional given an urban environment.

anon144114

The reason Americans love the Imperial (American) system of measurements is because they think it's American, When I was traveling through the states and told them they were using British Imperial their jaws hit the floor; they genuinely thought it was American!

As for it being long forgotten in the UK, you're very wrong. We still use miles and MPH to measure speed, road signs are in yards, and people measure there weight in pounds and ounces and we buy milk in pints.

anon131665

Whoever made the reference to the next town in time, I have to say I find such references annoying. You seemed to insinuate that this reference to time was more accurate then using a distance. It tells me absolutely nothing about how far away the next town is if you use a time, but don't reference a speed. I prefer to know a distance to a time.

anon125456

If people learn any measurement system, it is easy to learn any other measurement system. It's those who haven't learned any measurement system at all who usually plead "I'm from Europe/the States, I only know metric/english" but then can't communicate in that one either.

amypollick

@Anon119554: You got it. Hit the nail on the head. People can't even measure ingredients in measuring cups, and they can't do fractions or decimals (rendering both imperial and metric useless). Not only that, they also are incapable of calculating price per pound. Example: Ham is \$6 per pound. They want half a pound, and wonder why it costs \$3. I've never seen anything like it.

anon119554

I like the comment that it is not a matter of knowing either metric, imperial, or both, but that most people know neither. This may be why most of us are forced to buy pre-packaged anything instead of usable quantities.

Try visiting a "real" fish counter, butcher shop, fabric shop, lumber yard, or any other place that requires human interaction, and you will see this:

"How much/many (pounds/yards/meters/grams/etc) would you like?"

"Ummmm."

Drives me nuts.

anon117516

Oh yes, and on the matter of "natural" measures, why does the rod vary in length by state? Or the hogshead? (And is this the size of an "average" hog's head, and why is alcohol measured in a different version of hogsheads than other liquids?)

Why don't we use cubits (approx. the length of the arm from the elbow to the fingers)? Why are horses measured in "hands" (whose hand is used for the measure) but dogs in inches? Horsepower of an engine-clydesdales, Arabians, or shetland ponies?

And the inch at one time was defined as the length of an "average" man's thumb, or three "average" barleycorns laid end to end (how many cityfolk know how long a barleycorn is?), or now by law, 2.54 cm (exactly)?

How many cityfolk know how big a peck is, or how many tomatoes it will hold? Why are bushels different for every sort of produce? Why is gold measured in troy ounces and lead in "standard" ounces, but diamonds in carats? (I can't even spell the word for standard ounces). Yet the US adopted metric money (mils, pennies, dimes, dollars).

There is absolutely nothing "natural" about the United States Customary Units (look that phrase up to see our "natural system" at its finest).

It is a specious argument. The next town up the road from here is ten minutes away whether you measure it in miles, nautical miles, rods, furlongs, or kilometers.

anon117507

Concerning "natural measurement": A natural measurement to the next town up the road (10 miles/16 km) is not measured in distance at all, either English or Metric; it is 10 minutes away. No conversion necessary.

Metric units are "human" or "natural" as well. The meter used to be defined as 10,000,000th of the distance from the equator to a pole, temperature makes much more sense than Fahrenheit (which I can't even spell), with water freezing at 0 degrees and boiling at 100.

The only reason we still use nautical miles in maritime and aviation measurement (which are different than statute miles) is because of the maritime adage "a minute (of arc) is a mile (at the equator), and the metric system of grads for arc measurements has not been widely adopted.

anon116168

If the U.S. is the greatest nation in the world, then why is America's youth ranked 12th in science among developed nations? I would directly attribute this to the lack of the metric system being the main system of measures. Oh, and I'm from the U.S.

The argument that it's because we "prefer a challenge to test our moxie" is blatant ignorance. Oh, and the reason we stopped Metrication is because Reagan pulled the plug on the operation because he was running out of money because he wasted it on things like the War on Drugs and other futile efforts.

anon113159

The so-called English system is more "human" in scale and closer to "natural measurements." The problem is not that it's a problem to know the English system or the metric system or both. The problem is that when it comes to everyday applications, most people know neither, but resort to "natural measurements" or "reckoning." The metric/english argument is usually only a smokescreen.

By the way, navigation is by degrees. Time is in increments of 1, 60, 24, 7, 12, 4, and 365. The French wine industry still uses romantic names like "magnum" and "jeroboam."

anon112495

We learn different measuring and counting systems to relate better to the world around us. Contrary to the notion that "everyone, everywhere" uses the base ten metric system, consider these examples. Computers use the binary system.

Time is measured in various units of 365, 52, 12, 4, 7, 24, and 60. Navigation uses degrees. Natural phenomena like earthquakes and large storms are measured by magnitude. Horsepower still conveys some meaning in relation to car power. The good old French wine industry also still uses a variation of the Imperial system (pints, magnums, jeroboams, etc.)

There are many cases in which the metric system fails to communicate meaning, and in those cases we humans usually resort to natural measurements.

anon109379

Biggest fact ever: SI was proved to be more suitable because it is more logical in all fields. That's why the US adopted it officially for professional fields. One day, America will switch to metric and become like the rest of the world.

anon108066

America was built on the Imperial system. We are the greatest nation on the face of the earth. Perhaps the rest of the world should switch to the Imperial.

Fact: The conversion from the roman 5000 foot mile to the 5280 mile was due to the length of a furlong. The queen wanted the mile to be divisible by a yard. That is history that you don't get to enjoy with the metric system (SI if you want to sound intelligent).

The idea that the Imperial system is too hard is acceptable if you are not an American. Americans prefer a challenge to test our moxie, and if that means understanding a now ancient system of measure, one that we will continue to build the greatest nation on the face of the earth with, then so be it.

anon90514

i learned the imperial system first and then the metric which is so much easier. i wish the US would just switch over. our system is so complicated.

anon74333

It's a sad shame that the U.S. hasn't switched to SI. I am much more familiar with the imperial system, the good 'ol pound, mile, gallon. I also understand how completely stupid it is.

What makes me angry is that my school didn't force more of the metric system on me. It makes complete sense and only requires a small bit of memorization. It will be a little annoying when they switch, but I will be very happy if i live to see the day here when they do finally switch.

And I'll get used to it just like everybody else will.

anon73186

As long as right wing fanatical crazies squawk like frantic chickens, the US is not likely to join the metric system any time soon.

anon73185

As a teacher who teaches only the metric system, using a 30 cm ruler, roughly equivalent to 1 foot in the imperial system, is no more problematic using centimeters as units than it would be using inches. In my experience, multiplication has nothing to do with basic measurement on a limited scale while teaching young children.

anon66962

America has made efforts to switch in the past. There had been a large fear during the cold war that we would all become communist if we started using it. This is only one small example of why we have stayed with the imperial system. I would argue the need to switch to the metric system. It is far more logical, widely used and practical. It is already common practice for many Americans and to switch would clear up much confusion. 100 years from now will future Americans wonder why we had persisted with such an outdated system? I would hope so.

anon56711

Americans should start using SI and stop being stubborn.

anon47043

I disagree. While the American system is harder to understand, I have memorized many of the conversions and can tell you that a mile is 5,280 feet, 16 ounces is a pound and the like. The metric system, on the other hand, while simpler, is different to me and I prefer to go with what I already know. In studying the system in science I get all confused and must turn to a chart of the measurements. Perhaps I have not studied it enough, or perhaps I just don't like change which is highly probable, but I like the standard system better than the metric system. I hope the US continues using it.

anon36980

I started school learning imperial measurements in NZ; the metric system was introduced mid way through. The metric system is a lot more logical and therefore easier to learn than the imperial (or standard) system so people should not be reluctant to embrace it. At nearly 50 I still calculate kg to lbs and miles to km in my head. It is really not difficult to make the transition.