Grams vs. Ounces

[DeeAnna]

...If the imperial system wasn't precise, the US would have switched a long time ago, that wouldn't even be a question. Or so I believe.

I agree that if you have a specific scale, the precision of the measurements done by that scale doesn't change whether it's set to show grams or weight-based ounces. It's a misconception that the scale's precision is better or worse depending on the units you're using.

But I don't think I've ever changed anyone's mind whenever I've attempted to explain this, so I've pretty much given up trying anymore. And, in the end, it's really a moot point for most people, unless you're a practicing engineer, scientist, or statistician and really do Need to Understand these Things.

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On the other hand, I do think there is a tendency for people to think about numbers in certain ways. Some numbers seem "easier" than others. And that does affect what type of units one might want to use.

I'd venture to say most people perceive a weight of 9 grams as being "easier" to measure and understand than the equivalent weight of 0.32 ounces. And conversely, 100 ounces can appear "easier" than 2830 grams or 2.83 kilograms, even though these weights are equivalent.

This is something like the old psychology experiment where you pour a certain amount of water in a tall skinny glass and pour the exact same amount of water in another glass that is wide and low. If you do this in front of a young child and then ask them to tell you which glass has more water, the child will say the tall skinny glass has more water in it. Up to a certain age, kids literally can't perceive there is no difference in the amount. They think there is because the shape is different.

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Science and engineering in the US is mostly based on the metric system. It's been that way for quite some decades now. Metric simplifies calculations done by computers and calculators, since metric isn't based on fractional numbers like Imperial tends to be, especially length measurements. One kilometer is 1000 meters, but 1 mile is 5280 feet. Which one is easier to remember?

Measurements in everyday life are largely Imperial in the US, but it's also true we aren't the only country that uses a fair bit of Imperial measurements in everyday life. People in the UK and Canada also talk about using Imperial (feet, pounds, ounces) and even older traditional units (stone), so if you want to poke fun at Americans, then include the Canadians and Britishers.

I'm an engineer and I can exist in both worlds fairly easily.

 

[MelissaG]

I also never understood why grams would be more precise than ounces, but the fact that this belief is widely spread among the soapmaking community made most of the content in english more accessible to me, since so many american soapmakers share recipes or advices for aditives in grams. As someone born and raised in Europe, the imperial system doesn't make any sense to me.

We kind of like to make fun of the imperial system in Europe, but I never heard anyone say it was not precise (it is more about it being random). When I got interested in soap making and read about the "grams are more precise" thing, I thought it was quite funny to assume a whole country's math and engineering is based on something not precise. If the imperial system wasn't precise, the US would have switched a long time ago, that wouldn't even be a question. Or so I believe.

The US is stubborn. They won't switch because they think they're right. And I'm an American. It drives me crazy. I was born in Canada and have dual citizenship. I can tell you from experience, grams is more accurate. The reason is that most scales don't go down that far and it's easy to overmeasure in the imperial system. I do grams for everything except soap because a gram or two here or there isn't going to matter much.

 

[ClaudiaO]

Hi all. I have seen stated in so many places that “grams are more accurate than ounces.” Many YouTubers say it as a point of fact. Ounces are no less accurate. If you have a scale that only measures whole ounces, the units will be less PRECISE (not less accurate). But, I think most scales that measure grams or ounces will also measure at least to tenths of an ounce (my scale measures to hundredths.) My scale also measures to the nearest half gram.
Here is what I mean. Say I want to measure 10 ounces of something. (Not fluid ounces - Ug, I hate our stupid unit system with fluid ounces!) 10 ounces = 283.495 grams. My scale measures to .01 ounces, so I can measure 10.00 ounces - which is accurate within .28 grams. If I were to measure the same amount in grams, I would need to round up to 283.5 grams - and my measurement would be accurate within 0.5 grams. My scale will measure to a greater level of precision in ounces than it does in grams. The units are really no more or less accurate - it is the scale and the precision of the units that matter. If your scale only measured WHOLE ounces and WHOLE grams, than yes, it would be more precise to measure in grams.
All this being said… I use grams when making soap… because I just do. Although I track prices for everything I use in ounces. Because I just do.

I certainly could be wrong but in this scenario isn't the difference .005 grams (283.5 g minus 283.495 g) making the gram weight more precise?

I grew up with the metric system but have lived in the states so long that ounces, cups, pints, gallons, 12" to a foot and 16 oz to a pound are very familiar to me.

I just have to chuckle and wonder why Americans are so opposed to the metric system. When asked they can often tell you how many meters in a kilometer but do not know how many feet in a mile. I know the answer to both.
There seems to be so much to remember with oz. to pounds, cups to a pint, quart, gallon, inches to a foot and the numbers are all different.
Also in favor of military time.

Doubt the change will ever happen and I'm okay with that. However, I do weigh everything in grams.

Just my .02 cents.

PS: other measurements are quite odd as well. I learned the hard way that a 2x2 piece of lumber is NOT 2x2.

 

[AliOop]

It's not my impression that Americans are opposed to the metric system per se, so much as the cost to convert everything to the metric system. Then there is simply the distaste for change, and how many find it easier to live with low-level dysfunction than to go through the painful process of change in order to get to something better.

I for one wish we had bitten the bullet back in the 60s or 70s when it seemed like we were going to do it. It would now be 50+ years in the rearview mirror, like telling kids today about our old phones that were attached to the wall, with no caller ID or voicemail or texting.

 

[ClaudiaO]

For me it's more about weighing ingredients, not so much whether in oz. or grams. Would love baking recipes by weight rather than cups.

Use whichever method works best as long as you use a scale.

 

[Vicki C]

I certainly could be wrong but in this scenario isn't the difference .005 grams (283.5 g minus 283.495 g) making the gram weight more precise?

Well, that’s precisely my point - my scale measures to .5 grams, and (if I change units) to 0.01 ounces which is a smaller unit than 0.5 grams - it’s 0.28 grams. But really my point is that the relentless repeating of “grams are more accurate” makes me a little batty.

 

[justsomeguy]

But really my point is that the relentless repeating of “grams are more accurate” makes me a little batty.

I read it as "I'm more accurate using grams" and all the battiness goes away

 

[Vicki C]

I read it as "I'm more accurate using grams" and all the battiness goes away

Haha that’s perfect. Thank you.

 

[melinda48]

I believe a kilometer is 3/5 of a mile. And don’t worry, no way am I converting kg to pounds using a 2:1 ratio for soapmaking. I formulate everything in grams. What I was saying about rough conversions in my mind is more what I use when I see a person’s weight in kg and I need to make it make sense in my American mind. Or, when I’m outside of the US and see a distance measured in km….a rough conversion is enough for me to make an estimation of how far away something is. I’m much more precise when making soap.

Ditto!

 

[2lilboots]

I measure in ozs. I know my soap recipe by heart, although I write it up for every batch I make.

 

[Nona'sFarm]

I read it as "I'm more accurate using grams" and all the battiness goes away

Yes! that is how I interpret it, too.

And yes, I agree with @AliOop, what stopped the U.S. from converting was the cost to convert. I used to work for a manufacturer. Everything was measured in pounds. The raw materials coming in and the finished goods going out were all measured in pounds. The machinery had scales built into it to get the right amount of each ingredient into the mix, not to mention the built in warehouse and forklift scales. To change to metric all of that machinery would need to be retooled. Multiply that by the number of companies in the same boat and you start to see the magnitude. Granted it would be a one time cost, but companies trying to protect their bottom line are definitely going to resist that kind of change.

What was interesting, though and a fun challenge for me, was that we had non-U.S. facilities, too. They not only used different currencies, but also, most used the metric system. So sometimes, when doing cost analysis, I not only had to convert to the same currency, but also to the same unit of measure.

 

[MelissaG]

The reason I say it isn't the cost is because most things need to be labeled in grams and oz anyway. Converting the amounts wouldn't take that much time.

 

[Benjamin]

Growing up with “metric is coming,” I love this discussion. I think distance in miles, carpentry in feet/inches, and baking/soap in grams.

 

[AliOop]

The reason I say it isn't the cost is because most things need to be labeled in grams and oz anyway. Converting the amounts wouldn't take that much time.

The weighing and labeling is one of the last steps. As @Nona'sFarm said, the big issue was retooling all the machinery in the production facilities that have cutters, loaders, and all kinds of physical parts that were designed around the Imperial system. Many factory production processes are now highly computerized, but a good portion isn’t.

So there would be huge expenses involved there - kind of like laying all new railroad tracks to change from narrow gauge to the wider one. Perhaps not as much now with all the computerization, but still not minimal.

 

[paradisi]

The weighing and labeling is one of the last steps. As @Nona'sFarm said, the big issue was retooling all the machinery in the production facilities that have cutters, loaders, and all kinds of physical parts that were designed around the Imperial system. Many factory production processes are now is highly computerized, but a good portion isn’t.

So there would be huge expenses involved there - kind of like laying all new railroad tracks to change from narrow gauge to the wider one. Perhaps not as much now with all the computerization, but still not minimal.

Plus, math is *free*.
Denote in both systems on the labels.
There's no benefit to switching machinery in hundreds of thousands of businesses when math and current labeling will do.