All four are regulations rather than conventions, and the net quantity has a position and a type size.
The ingredient declaration
The name of each ingredient, in descending order of predominance, with enough prominence to be likely to be read and understood by ordinary individuals under normal conditions of purchase.
The name and place of business
The manufacturer, packer or distributor, with a street address, city, state and ZIP. FDA tells small makers directly that a post office box or a website address will not do.
The net quantity of contents
On the principal display panel, within the bottom 30 percent of the panel, in a line generally parallel to the base the package rests on. Weight in avoirdupois pound and ounce; fluid measure in US gallon, quart, pint and fluid ounce.
And the type size for it
Not less than 1/16 inch high for a principal display panel of 5 square inches or less. Not less than 1/8 inch for a panel above that up to 25 square inches.
The small package relief that applies to almost everything here
The bottom-30-percent placement is waived where the principal display panel is 5 square inches or less. A 30 mL Boston round is comfortably inside that, so on most of this range you keep the type size requirement and lose the placement one.
What is not on this list
A barcode, an expiry date, a batch code and a website are all things you may want and none of them are what makes the label compliant. Build the four requirements into the layout first and fit the rest around them.
Why this is a container decision
Four mandatory elements at a specified minimum type size is a measurable area. On the smallest containers in this craft it is most of the label, which is the real reason to settle the label before ordering the bottle.
References
21 CFR 701.3, the cosmetic ingredient declaration: the label "shall bear a declaration of the name of each ingredient in descending order of predominance", with the alternative grouping at (f) allowing ingredients at not more than 1 percent, and color additives, to be listed without respect to order; and at (b) a requirement that the declaration appear with such prominence "as to render it likely to be read and understood by ordinary individuals under normal conditions of purchase".
law.cornell.edu21 CFR 701.12, the name and place of business of the manufacturer, packer or distributor. FDA’s small business fact sheet states that a street address, city, state and ZIP are required and that a post office box or a website is not sufficient.
law.cornell.edu21 CFR 701.13, net quantity of contents. It is declared on the principal display panel "within the bottom 30 percent of the area of the label panel in line generally parallel to the base on which the package rests", a placement waived where that panel is 5 square inches or less; weight in avoirdupois pound and ounce, fluid measure in US gallon and its quart, pint and fluid ounce subdivisions; type not less than 1/16 inch for a panel of 5 square inches or less and 1/8 inch above that to 25 square inches.
law.cornell.eduFDA,
Small Businesses & Homemade Cosmetics: Fact Sheet. Cosmetics and their ingredients, other than color additives, do not need FDA approval before sale, and the manufacturer is "legally responsible for making sure your cosmetics are safe and properly labeled". Manufacturing at home is not against the law, but the product must not be adulterated by the conditions it is made in.
fda.gov 