Nanodropper is a one-size-fits-most for a specific bottle type. Please take time to read this page carefully to ensure that Nanodropper is right for your medications. Please contact us at support@nanodropper.com for further questions regarding the fit!

Traditional eye drops

Nanodropper was made for multi-dose eyedrop bottles that have a screw-top cap like those in the picture below. While the volume of the bottle does not matter, the diameter of the threads that the cap goes onto is very important. Most bottle threads will have an “imperial” diameter of approximately 9/16in (0.5625in or ~15mm). These are the bottles that Nanodropper is compatible with. There are a few bottles that have a “metric” diameter of 14mm (~0.55in), 13mm (~0.5in), or smaller. These smaller sizes will be coming soon!

Examples of multi-dose bottles, not intended to be a comprehensive list.
Do not assume your bottle is compatible just from this image, many bottles look the same but will be different sizes.

You can test if your bottle will fit our current-sized adaptor using the Compatibility Guide linked in the button below. You will find a print-out guide that will allow you to measure your bottle as shown in the image. If you do not have a printer, there is an alternative option on the guide as well.

Please note that the same type of medication is sometimes packaged in different types of bottles. You may even be given a different type of bottle on a refill for the same prescription. It is important that you use the compatibility card to test every bottle that you intend to use the Nanodropper with. If you would like to know if your type of medication is produced in a compatible bottle, email us at support@nanodropper.com.

Nanodropper will NOT fit preservative-free drops

These are commonly used for dry eye conditions and have “PF” in their name.


Our 100% fit promise

We want you to feel confident in purchasing our products. If you purchase a Nanodropper and find that it does not fit your bottle as described in this guide, please take a picture of your medication bottle in the compatibility card or on a plain background, and send it to support@nanodropper.com for a refund of your product. Shipping & Handling fees are non-refundable. Find our full refund and return policies here.

Want to receive exclusive offers and be the first to hear about sales and product updates? Subscribe below!

Skip to content