Brimful Capacity vs Labeled Volume: Matching a 30ml Bottle’s Fill at the Design and Sample Stage
2026-10-28
Brimful capacity is the volume a cosmetic bottle holds when filled to the very top of the neck; labeled volume is the content shown on the product. A 30ml bottle is therefore designed to hold more than 30ml, and that margin absorbs the space taken by a dropper or pump and the filling tolerance. Under Korea's Regulation on Cosmetics Safety Standards, the average content of three units must be at least 97% of the labeled amount, so the fill target should be set from the labeled volume, the actual bottle's brimful capacity and the volume the components displace. JeongwooCos confirms the target capacity, formula and dispensing method at consultation, matches the bottle with a dropper or pump through design and mold review and a basic sample (shape, capacity, neck and compatibility), and can deliver the set assembled. This article covers the terms, the legal standard, and what is checked at each stage when working with JeongwooCos.
Labeled volume, brimful capacity and fill point are different numbers
1. How does brimful capacity differ from labeled volume?
Labeled volume is the amount sold to the consumer; brimful capacity is the maximum the same bottle holds when filled to the top. Glass bottle drawings define a bottle by its nominal volume together with its brimful capacity and tolerance, or by the volume at a set fill point.
| Term | Meaning | Who uses it | How to check |
|---|---|---|---|
| Labeled volume (content) | Volume or weight shown on the product, e.g. 30ml | Brand, label and carton | Required on the outer packaging under the Cosmetics Act |
| Brimful capacity | Volume when filled to the top of the neck | Container drawings, filling line | Weight difference between the empty bottle and the bottle full of water |
| Fill point | Height of the liquid when the labeled volume is filled | Filling line, QC | Measure from the base to the liquid level after filling the labeled volume |
| Headspace | Empty space between the liquid and the neck opening | Component fit, transport stability | Brimful capacity minus fill volume |
A spirits drawing may list a 750ml bottle with a brimful capacity of 780±8ml; in the same way, brimful capacity sits above the labeled volume and carries a tolerance. Brimful capacity and tolerance differ by cosmetic bottle, so confirm them at the sample stage.
How JeongwooCos handles it: consultation and design review
At consultation, JeongwooCos confirms capacity, shape, quantity and delivery date together with the formula's viscosity and the dispensing method you want, and proposes a bottle and component set. At design and mold review we prepare drawings, decide between an existing mold and a new one, and check shape and fit with 3D-printed prototypes before investing in a mold. Share the labeled volume, target fill and planned dropper or pump at this point, and bottle capacity and components can be reviewed together.
See manufacturing process and the formulation guide.
2. How much must a cosmetic be filled under Korean rules?
Three units are tested and their average content must be at least 97% of the labeled amount; if not, six more are taken and the average of nine must reach 97%. For a 30ml product, the three-unit average must be 29.1ml or more.
- Basis: the content standard for distributed cosmetics in the Regulation on Cosmetics Safety Standards (MFDS notice)
- The volume or weight of the contents must appear on the outer packaging under Article 10 of the Cosmetics Act.
- Because the rule uses an average, a wide filling spread means the target has to sit above the labeled amount to pass reliably.
3. The label says ml but the line fills by weight. How do you convert?
If the filling line works by weight, the target weight is the labeled volume multiplied by the specific gravity of the formula. For a 30ml serum with a specific gravity of 1.02, the labeled amount is 30 × 1.02 = 30.6g.
| Item | Example | Note |
|---|---|---|
| Labeled volume | 30ml | Value on the label |
| Specific gravity | 1.02 | Varies by formula; use a measured value |
| Labeled amount by weight | 30.6g | 30 × 1.02 |
| Legal floor (average) | 29.1ml (about 29.7g) | 97% of the labeled amount |
| Bottle brimful capacity | Drawing or measured value | Must exceed fill target + component volume + margin |
The gravity and figures above are illustrative. Set real values from formula measurements and sample bottles.
Leave room for the volume a dropper or pump displaces
4. Why does the formula overflow when a dropper or pump goes in?
When a dropper's glass pipette or a pump's dip tube enters the liquid, the level rises by the volume it displaces. If the gap between brimful capacity and fill volume is smaller than that displacement, the formula overflows at assembly.
- Weigh an empty sample bottle.
- Fill it to the top with room-temperature water and weigh it again; the difference in grams is roughly the brimful capacity in ml.
- Fill water to the labeled volume only and insert the actual dropper or pump.
- If it overflows or the level sits too close to the opening, decide whether to change the fill volume, pipette length or bottle size.
- Repeat with the real formula and record the fill height as the production standard.
How JeongwooCos handles it: samples and component sets
A JeongwooCos basic sample exists to confirm shape, capacity, neck and compatibility, which makes it the right stage to measure brimful capacity and fill height and to try the dropper or pump in place, as in the steps above. Glass pipette length and thickness can be customized, and essence pump output and return force are adjusted at the design stage. The agreed set can be delivered with caps, pumps or droppers assembled, and inspection checks bore, height and wall thickness as well as the seal when a cap or pump is fitted.
See the sample policy, parts anatomy guide and quality assurance.
Pipette length and neck finish have to match. See Neck Sizes: 18mm vs 20mm and Dropper vs Pump vs Cap.
5. What should you check and request when choosing a bottle?
Don't choose by labeled volume alone; confirm brimful capacity, tolerance and the fill height with the real components fitted, using samples. Two 30ml bottles of different shapes can have very different fill heights and headspace.
- Check capacity, dimensions, neck finish and compatible components on the product page first. For example, JeongwooCos 01S60-01 is 60ml, Φ42 × H96 with a standard 20mm neck, and takes a dropper, metal dropper, essence pump or mist pump (view cosmetic glass containers).
- When requesting samples, ask for brimful capacity, tolerance and the component combination you plan to use.
- Share the formula's specific gravity and target fill with the filler (OEM/ODM).
- Review formula-package compatibility separately, as in the CT testing checklist and recording method.
Where fill volume is matched when working with JeongwooCos
JeongwooCos production runs in six stages: consultation and requirements, design and mold review, sample production, mass production, quality inspection, and packaging and delivery. Brimful capacity and fill margin are set early, so checking the items below at each stage reduces overflow and short fills after production starts.
| Stage | What JeongwooCos does | What to check for fill volume |
|---|---|---|
| Consultation and requirements | Confirms capacity, shape, quantity, delivery date, formula viscosity and dispensing method; proposes a bottle and component set | Labeled volume, specific gravity, target fill, planned dropper or pump |
| Design and mold review | Prepares drawings, reviews existing or new molds, checks shape and fit with 3D-printed prototypes | Whether the bottle capacity, neck and components leave a fill margin |
| Sample production | Basic sample (shape, capacity, neck, compatibility), decoration sample, approval sample | Measured brimful capacity, fill height at labeled volume, overflow when components are fitted |
| Quality inspection | Measures bore, height and wall thickness; checks the seal with caps and pumps fitted | Production dimensions matching the approved sample |
| Packaging and delivery | Delivers with caps, pumps or droppers assembled; packs safely and ships | Share the assembled component spec with the filling line |
If you are still deciding between 30ml and 50ml, start with the Serum Bottle 30ml vs 50ml guide. Base MOQ varies by product and is typically 3,000-5,000 units, and a basic sample takes 7-14 days on average (MOQ and lead time guide, OEM/ODM scope).
Frequently asked questions
Does a 30ml bottle hold more than 30ml?
Yes. Brimful capacity is designed above the labeled volume, and the margin absorbs component fit and filling tolerance. The exact figure has a tolerance by product and production lot, so confirm it with samples.
Can I fill slightly less than the labeled amount?
The average must be at least 97% of the labeled amount. If three units fall short, nine are re-tested, so set the target at or above the labeled amount to allow for filling spread.
How can I measure brimful capacity myself?
Weigh the empty bottle, fill it to the top with room-temperature water and weigh it again. One ml of water weighs about 1g, so the difference is roughly the brimful capacity. Measure several bottles to see the average and spread.
What can I confirm with a JeongwooCos sample?
A basic sample confirms shape, capacity, neck and component compatibility. Basic samples are free and take 7-14 days on average; share the dropper or pump you plan to use and your target fill, and the fitted set can be checked too.
References
- Regulation on Cosmetics Safety Standards - Korean Law Information Center
- Cosmetics Act Article 10 (labeling) - Korean Law Information Center
- How to Read a Glass Spirit Bottle Technical Drawing - nominal, brimful and fill point example
Match fill volume and components at the sample stage
Include the product group (bottle, jar, components), labeled volume, formula gravity and viscosity, planned components, quantity and target delivery date. JeongwooCos proposes a bottle and dropper or pump set and sets out what to confirm with the basic sample. Request a sample or quote
