The super-slow conversion of the U.S. to metric (2025) • Hacker News Board

Re: The super-slow conversion of the U.S. to metric (2025)

#181

Post by cucumber3732842 » Wed, Jan 21, 2026, 4:36 PM UTC

relaxing wrote: post #123

cucumber3732842 wrote: post #118

Earlier quoted context omitted.

The unit itself doesn't actually matter. Even industries with the least precision set their stuff up with so much precision that the unit you use basically doesn't matter. Your machine may spit out widgets that are plus or minus an inch. But when you set up the machine you set it up to the 1/16 regardless. Swapping all that to metric doesn't actually change anything other than the number the guy setting it up dials i…

1/16” is just over 1.5 mm, so yes, the guy setting the machine in millimeters is giving you more precision. In the real world measurements aren’t just abstract figures you can move around losslessly. I have a socket set in half-millimeter sizes for the absolute plague of cheap bolts and nuts that are being manufactured with obscene levels of slop.

You're missing the point.

The guy buying the widgets doesn't care because he's expecting a widget that's plus or minus dozens of the unit the machine is being set to. The setting is just as precise as it is in order to set the fat part of your output curve over the middle of your quality control pass range.

The machine might not even be calibrated in a direct measurement, it might be calibrated in a secondary measurement. Like tons of force or rpm or cycle speed or something that then translates to the dimension of your output part.

The units on machines mostly only exist for calibration. Beyond that they can just be made up "my amp goes to 11" type scales because they're so divorced from the outputs, either in precision (or are literally indirect as described above) that you "just have to know" that if you want a "X" widget you'll actually set the machine

Tons and tons and tons of stuff in our world is even intentionally spec'd out in this manner. A 14" tire rim is not 14, there's a tolerance. A 3" pipe isn't 3". These are all just nominal sizes. Just about everything in our world is nominally sized. A nut and bolt manufacturer doesn't care whether they're making 12mm or 1/2 on a given day. Those are just nominal sizes, arbitrary names, in their minds. It doesn't matter whether the factory runs on metric or imperial or something else because they're just shooting for an arbitrary number.

The only time your unit really matters is when interfacing with other parties and it only matters insofar as you need to know what each other are uses.

Re: The super-slow conversion of the U.S. to metric (2025)

#182

Post by SideburnsOfDoom » Wed, Jan 21, 2026, 4:38 PM UTC

sarchertech wrote: post #38

The problem is that Fahrenheit is a bit more convenient for describing the weather. Inches and feet are a bit more convenient for measuring human scale things and for being easily divisible by more numbers. And we’re used to the rest of it. Unless someone comes along and forces it on you, for the average person, there’s not enough incentive to switch.

> Inches and feet are a bit more convenient for measuring human scale things

nope, this is mere familiarity. You find it more natural because you're more used to it, nothing more.

There is nothing convenient about a system where "below zero" and "below freezing" are not synonyms. Or at least that's how I find it. because of what I'm used to. But at least I realise that might be a fact about me, not a fact about the world.

Re: The super-slow conversion of the U.S. to metric (2025)

#183

Post by [deleted] » Wed, Jan 21, 2026, 4:38 PM UTC

walthamstow wrote: post #136

yurishimo wrote: post #21

Earlier quoted context omitted.

Everyone who wants to collaborate internationally is already doing it. Science in the US is entirely metric. Construction and domestic measurements are the two biggest holdouts and honestly they’re both negligible. Given the proliferation of global manufacturing, most businesses are converting at the end before retail for US customers. If the government was competent, they could rip off the bandaid and everyone would…

re construction, we use 8x4ft sheets of timber in Britain still, same as before, we just call them twelve-twenty-by-two-four-forty now.

[deleted]

Re: The super-slow conversion of the U.S. to metric (2025)

#184

Post by zahlman » Wed, Jan 21, 2026, 4:39 PM UTC

nayuki wrote: post #173

ericmay wrote: post #86

Earlier quoted context omitted.

> Yeah, we went over the Metric System that whole year. I can still sing the "Metric Family" song from the film on metric units ("Kilo", "Milli", etc.). And to my young an impressionable mind, the U.S. was joining the rest of the world "Free World" in a kind of Star-Trek-like casting aside of the old things that divided us—joining each other with a focus on progress, science, space… I’ve always found this peculiar be…

> I find the imperial system fits in better with that warmth of humanity Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless names and numbers to memorize compared to kilo = 1000, milli = 0.001. > in favor of cultural uniqueness and fun over conformity You're writing in impeccable English. As we know, English is an international language and most definitel…

> Right, so you enjoy warmth such as

... Yes, I think that was unironically exactly the point.

> You're writing in impeccable English.

Which is a ornery bastard of a language with more exceptions than rules. It's about aesthetic, not popularity.

> Would you like to use a monetary system based on pounds, shillings, and pence

I wouldn't be surprised.

Your entire comment comes across like you think you're exposing contradictions that really just aren't contradictions at all.

Re: The super-slow conversion of the U.S. to metric (2025)

#185

Post by TheCoelacanth » Wed, Jan 21, 2026, 4:39 PM UTC

threemux wrote: post #62

I'd part with cups and teaspoons/tablespoons and the like, but you'll pry inches/feet/yards and fahrenheit from my cold, dead hands. They're both more convenient for daily use. I think I'd prefer to keep miles as well but I don't have a good reason for that one. Fahrenheit has more precision without using decimals for the thing 99% of people are using temperature measurements for: air temp. Where I live, we generally…

The extra precision is fake.

They might have measured precisely at the weather station, but local variation in temperature makes that extra precision meaningless unless you are located exactly where the measurement happened.

Even in a climate controlled room, there will be a degree or two of variation between different parts of the room.

Re: The super-slow conversion of the U.S. to metric (2025)

#186

Post by [deleted] » Wed, Jan 21, 2026, 4:39 PM UTC

nayuki wrote: post #173

ericmay wrote: post #86

Earlier quoted context omitted.

> Yeah, we went over the Metric System that whole year. I can still sing the "Metric Family" song from the film on metric units ("Kilo", "Milli", etc.). And to my young an impressionable mind, the U.S. was joining the rest of the world "Free World" in a kind of Star-Trek-like casting aside of the old things that divided us—joining each other with a focus on progress, science, space… I’ve always found this peculiar be…

> I find the imperial system fits in better with that warmth of humanity Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless names and numbers to memorize compared to kilo = 1000, milli = 0.001. > in favor of cultural uniqueness and fun over conformity You're writing in impeccable English. As we know, English is an international language and most definitel…

[deleted]

Re: The super-slow conversion of the U.S. to metric (2025)

#187

Post by zahlman » Wed, Jan 21, 2026, 4:40 PM UTC

ericmay wrote: post #180

nayuki wrote: post #173

Earlier quoted context omitted.

> I find the imperial system fits in better with that warmth of humanity Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless names and numbers to memorize compared to kilo = 1000, milli = 0.001. > in favor of cultural uniqueness and fun over conformity You're writing in impeccable English. As we know, English is an international language and most definitel…

> Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless facts to memorize compared to kilo = 1000, milli = 0.001. Most of life is just useless facts, I think it's fun and I enjoy it. > You're writing in impeccable English. As we know, English is an international language and most definitely not the pinnacle of cultural uniqueness or non-conformity. Why not a…

Basis points are a ratio (1/100 of a percent), not an amount.

Re: The super-slow conversion of the U.S. to metric (2025)

#188

Post by llsf » Wed, Jan 21, 2026, 4:40 PM UTC

sarchertech wrote: post #78

jventura wrote: post #54

Earlier quoted context omitted.

As someone born and living in a country that uses the metric system, I do not understand a bit of what inches and feets mean. Tell me something has 10-15 cm, and I know what it means. I measure 173cm, I know what one meter is about. 5'10? What the hell is that?! 5 feet and 10 inches? Some people have small feet, some have larger. And what is an "inch"? :) Oh, and fahrenheit, what the hell it means? 0ºC means ice, 100…

That’s not what I’m saying at all. I’m saying that a system where the majority of air temperatures in the vast majority of the country fall between 0 and 100 is slightly more convenient than one in which they fall between -17 and 37. 0 is really cold it doesn’t frequently get colder than that in most of the country. 100 is really hot, in most places it doesn’t get hotter than that. Feet are slightly more convent for…

Was in Fairbanks last weekend and it was -15F. So, having Fahrenheit staying positive for weather in US, is not really an argument. I am fine with Celsius based on water (0 freezing and 100 boiling). But I get that changing is confusing when you have adjusted your whole life to a system. If taught at school and displayed, in half a generation we could move to metric. Like others said groceries are already there.

Re: The super-slow conversion of the U.S. to metric (2025)

#189

Post by spogbiper » Wed, Jan 21, 2026, 4:40 PM UTC

ivan_gammel wrote: post #84

sarchertech wrote: post #56

Earlier quoted context omitted.

On the Fahrenheit scale, the majority of daily temperatures in the vast majority of the US fall between 0 and 100, which is -17 and 37 Celsius, and it’s more granular without introducing a decimal point.

In metric world nobody cares about decimal points in temperature outside. Measuring precision is not that good because of wind, humidity, exposure to sun etc. We just don’t need that granularity, so it is really hard to understand why would you need that. Is there really any difference between 56°F and 57°F that you can feel and want to measure? And choice of 0/100 for weather is absolutely baseless. You do have belo…

below zero days are really really crazy cold and above 100 days are really really crazy hot. I don't think the fact that things occasionally exceed the 100 point "normal" range makes it less useful, if anything the out of bounds numbers emphasize the severity of the temperature. it's common where I grew up in the midwest US to hear "wow its going to be BELOW ZERO" as a way to express extreme cold

Re: The super-slow conversion of the U.S. to metric (2025)

#190

Post by briffle » Wed, Jan 21, 2026, 4:43 PM UTC

AlotOfReading wrote: post #153

threemux wrote: post #62

I'd part with cups and teaspoons/tablespoons and the like, but you'll pry inches/feet/yards and fahrenheit from my cold, dead hands. They're both more convenient for daily use. I think I'd prefer to keep miles as well but I don't have a good reason for that one. Fahrenheit has more precision without using decimals for the thing 99% of people are using temperature measurements for: air temp. Where I live, we generally…

Even in construction, feet/inches/yards kinda sucks. 1:10 scale drawings are painful to do manually, division by 2 is a bit erratic, and bolt sizing is a horrible mess. Metric bolts are nice and consistent. With you on temperature though.

My wife was a surveyor in a past carreer. We have a tape measure in the garage that measures to the nearest hundredth of a foot. It is just so weird to see. Forcing decimal on a measurement that does not normally have it just makes me uncomfortable.

https://surveysupplyinc.com/lufkin-12-foot-hi-viz-engineers-...