# Grams or oz?????

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#### Cherrydene soapy

##### Well-Known Member
Afternoon soap makers, I have just made a new soap, my soap scales only weigh in full numbers when using grams eg. 48 grams not 48.15 grams. The grams do go up in 1 gr increase. My oz does have a decimal point but only in multiple of 5’s eg. 6.75 oz not 6.79. When using the soapcal which is fabulous now I am getting used to it, it calculates the weight of my oil in oz and grams. My question is, am I better off using oz and rounding up eg. 6.79 to 6.80 ( using my school maths, if it’s 5 or more round up, less than 5 round down) or using grams with the same method? Same applies to my lye and water thanks from a totally confused soapie

#### Kamahido

I just use grams, as I like whole numbers.

#### shunt2011

##### Moderator Emeritus
Moderator Emeritus
I too weigh in grams. I round up for oils and butters and down for lye. So, 48.15 grams I would do 48. Bit, 48.51 I would do 49.

#### Marilyn Norgart

##### Well-Known Member
good question!! I have been rounding up for oils and down for lye also but its been in the back of my mind--hoping I was doing it right and wondering when I would start having issues . I was also wondering if I just bought a bad scale

#### atiz

##### Well-Known Member
0.05 oz = 1.42 g, so if your scale's precision is either 0.05 oz or 1 g, then you will be more precise if you measure in grams. A fraction of a gram is very little --- for a batch of 1-2 lb. or more it is quite negligible (considering the SAP values are averages anyway).

#### dibbles

##### Supporting Member
I weigh in grams. I round down for both lye and oils, the reason for that being I usually use mica in oil for colorant and the oil is not taken from the batch oils. Also, as @atiz mentioned, a fraction of a gram in a whole batch is negligible.

#### Loralei

##### Well-Known Member
When I started making, I used oz... now that I understand more, I have switched to grams, and everything consistently comes out better.. if I were you, I would run your recipe through a calculator again, using grams, so that you have the most accurate information, and results.

#### Paulie

##### Well-Known Member
I like grams, more accurate. I also like formulas with percentages instead of ounces or grams.

#### midnightsoaper

##### Well-Known Member
I use grams and round down for lye too.

#### DeeAnna

##### Well-Known Member
When people made soap with fairly inaccurate dial-type kitchen scales (it's what my grandmother used), it made a lot of sense to "round up for fats and round down for lye." It's not that important now that we use scales that are accurate to 1 gram or better.

If you're having trouble remembering the little ditty, don't worry. Just round numbers the way you learned in school and all will be fine. Honest.

edit -- For any one specific scale, the accuracy of the scale is same whether the units shown are grams or ounces. What is different is our mental perception of that weight. A weight in whole grams (291 grams to pick a number) seems different than the same weight in fractional ounces (10.26 ounces).

I use grams because I've used metric units all my professional life, so it's no big deal. I recommend grams to others for the perceptual reason I gave in the previous paragraph.

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#### Cherrydene soapy

##### Well-Known Member
Thank you so much

#### Obsidian

##### Well-Known Member
I use ounces and round to nearest if needed. Say it calls for 14.51 I would do 14.50 if it was 14.54 I would go to 14.55. I do this for oils and lye, I'm not concerned about a .01 difference .
The recipes I make myself are adjusted to use whole ounces though so its not really a issue.

#### atiz

##### Well-Known Member
For any one specific scale, the accuracy of the scale is same whether the units shown are grams or ounces. What is different is our mental perception of that weight. A weight in whole grams (291 grams to pick a number) seems different than the same weight in fractional ounces (10.26 ounces).

I don't understand this. Let's say you have the scale that Cherrydene is using: it shows grams with the precision of 1 g, and shows ounces with the precision of .05 oz.
Let's say you put on the scale something weighing 18.2 g (=0.64 oz). If your unit is set to grams, you'll see 18g; if your unit is set to oz, you'll see 0.60 oz. In the first case, you will be 0.2g off; in the second case, you will be 1.13 g off. So what does that have to do with our mental perception?

(I don't mean to hijack the thread; this is not really a practically relevant matter since it is about fractions of grams.)

#### DeeAnna

##### Well-Known Member
For an item that really weighs 18.2 grams or 0.64 oz -- If a scale in ounce mode rounds to the nearest 0.05 oz, the scale would round 0.64 oz up to 0.65 oz, not down to 0.60 oz.

#### SaltedFig

That's an interesting thought ... I'd always thought that the scale measurements go up once the weight had been reached - I'm off to check different sorts now! [Kitchen,soap and post] ).

Anyway, scales aside, I like grams (kilograms, heck, the whole metric mile ) ... because I can multiply and divide by 10's (so kilograms becomes grams by multiplying by 1,000 ... move the decimal point three numbers to the right ... done!)

Eg. 10 kilograms is 10.000 kilograms is 10,000 grams

#### atiz

##### Well-Known Member
For an item that really weighs 18.2 grams or 0.64 oz -- If a scale in ounce mode rounds to the nearest 0.05 oz, the scale would round 0.64 oz up to 0.65 oz, not down to 0.60 oz.
It depends on the scale (we used to have one that would just cut off the digits), but it is also besides the point. If your scale does the rounding correctly, you'll either be 0.2g off or 0.28g off with the same numbers (the difference is tiny, but it is a real one).
Anyway, this was only a theoretical point. Since I grew up in Europe, grams are more natural to me.

#### Micchi

##### Well-Known Member
While I use grams when actually making the soap, I have to admit that ounces comes more naturally to me, and when I'm formulating a recipe I'll usually pay more attention to the ounce measurements. I can just visualize the volume better in ounces, overall.

#### lsg

Staff member
Moderator
I use oz when making soap. I have a digital scale that measures to hundreths of an oz.

#### dibbles

##### Supporting Member
While I use grams when actually making the soap, I have to admit that ounces comes more naturally to me, and when I'm formulating a recipe I'll usually pay more attention to the ounce measurements. I can just visualize the volume better in ounces, overall.
Me too Micchi. Formulate in ounces and weigh in grams. I can visualize the volume better, and I know how many ounces my molds hold.

#### DeeAnna

##### Well-Known Member
I agree that 0.05 ounce or 1 gram are not mathematically exactly the same, but as far as this particular scale is concerned with the error inherent in its weighing mechanism, +/- 0.05 oz error in a given weight is statistically the same as +/- 1 gram error for the same weight. It honestly makes no difference whether you weigh in ounces or grams.

If a + or - 0.05 ounce resolution is not acceptable but a + or - 1 gram resolution is, the solution is to not using that particular scale at all. You're really not changing the accuracy in a statistically significant way if you use the scale in gram mode versus ounce mode. The answer is a better scale with a more sensitive mechanism that has at least one more significant digit for whichever weighing mode (ounces or grams) that you want to use.

I'm not sure I can explain this in a reasonably short and sweet version, so I'll stop here and simply say we're going to have to agree to disagree on this matter.

What bothers me far more than the ounces versus grams thing is when people use recipes in mixed units -- grams AND ounces -- in their recipes. That's an easy way to make major mistakes! My advice is to pick one set of units and stick with it when weighing ingredients.

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