1. Classification by Bottle Material: Glass, Plastic, Metal

Glass dropper bottles: Their primary advantage is their chemical inertness, meaning they won't react with the contents. They're ideal for storing active ingredients (such as vitamin C serums and retinol serums) or corrosive liquids (essential oils and pharmaceutical solvents).

Clear glass dropper bottles: Suitable for products that don't require light protection (such as regular toners and serums), making it easier to see how much is left.

Dark glass dropper bottles (amber, cobalt blue): With built-in UV protection, they effectively block UV rays, preventing oxidation and deterioration of ingredients, making them the best choice for light-sensitive products.

Plastic dropper bottles: Their primary advantages are lightness, drop resistance, and low cost, making them suitable for daily use and various office settings. However, care should be taken with the material to avoid chemical intrusion.

PP dropper bottles: They offer excellent heat resistance (can withstand temperatures ranging from -20°C to 120°C) and are chemically stable. They are commonly used to store basic skincare products (lotions, serums) or children's skincare products.

PET dropper bottles: They offer high transparency and a glass-like texture, but have poor corrosion resistance and are suitable for liquids without strong active ingredients.

HDPE dropper bottles: They are hard and resistant to pressure, making them suitable for topical medications or low-concentration industrial reagents.

Metal dropper bottle: mainly made of aluminum and stainless steel, with good texture and sealing. Because metal may react with acidic/alkaline liquids, its application range is relatively small.

2. Classification by dropper tip type:

Standard rubber-tipped droppers: The most common combination is a nitrile rubber or silicone tip with a glass or PP tube.

Integrated plastic droppers: The dropper and tip are injection-molded into one piece using materials such as TPE, offering cost control and design flexibility.

Screw-on dropper tips: The dropper tip itself is threaded and screws directly onto the bottle (no outer cap required). An internal sealing ring is required.

Anti-backflow droppers: A special internal valve prevents liquid from flowing back into the bottle when the tip is released, causing contamination or air bubbles. These require high technical requirements and come at a high cost.

Quantitative droppers: Special features (such as scales and flow-restriction mechanisms) allow for more precise, fixed dispensing of liquid.

3. Classification by Capacity:

Common capacities include 5ml, 10ml, 15ml, 20ml, 30ml, and 50ml. The smaller the capacity, the higher the precision required for the dropper.

Skincare dropper bottles: Dropper capacities typically range from 0.5ml to 2ml, allowing for a single application (e.g., 1ml of serum) to minimize contamination from repeated contact. These bottles often feature a threaded cap with a silicone seal for enhanced sealing. Some high-end models utilize a vacuum dropper design (without a straw) to completely isolate the bottle from air and extend the shelf life of the serum. Capacities under 30ml are suitable for small serums, while 50ml is suitable for lotions.

Pharmaceutical dropper bottles: Medicinal dropper bottles must meet pharmaceutical standards (such as USP and GMP certification). Sterility and accurate dosing are paramount.

Mostly made of borosilicate glass or food-grade PP, they can be sterilized at high temperatures (e.g., 121°C).

Droppers feature graduated scales (e.g., 0.1ml, 0.5ml) to ensure accurate dosing (e.g., for children's fever-reducing medications and eye drops).

Some come with dust caps to prevent contamination of the dropper tip. Suitable for use with oral drops, topical disinfectants, and ophthalmology/ENT reagents.

Essential Oil/Aromatherapy Dropper Bottles: These dropper bottles offer two key advantages, addressing the volatility and photophobia of essential oils:

They are almost always made of dark glass (primarily amber), which blocks UV rays;

The dropper has a thin diameter (approximately 2mm), allowing for precise droplet delivery (1 drop x 0.05ml), thus minimizing essential oil waste (which can lead to higher unit prices).

Common sizes include 5ml, 10ml (suitable for single essential oils), and 30ml (suitable for blends or aromatherapy blends).

Mostly made of borosilicate glass (resistant to strong acids and alkalis) or PTFE (extremely chemically resistant).

Highly accurate graduations (e.g., ±0.05ml) make them suitable for sampling laboratory reagents.

Various sizes available: 10ml, 25ml, 50ml, and 100ml (suitable for different experimental volumes).