Funnels

What Are Laboratory Weighing Funnels?

Laboratory weighing funnels are single-use antistatic polypropylene (PP) funnels specifically designed for the weighing-and-transfer step in analytical chemistry, pharmaceutical weighing, and sample preparation workflows. Unlike standard powder funnels, weighing funnels have one flat side that allows the funnel to rest stable on a balance pan during mass measurement, and a conical stem sized to the neck of a specific volumetric flask volume. After the sample mass is recorded, the funnel inserts directly into the flask neck, and the sample is transferred by tipping or rinsing—providing quantitative, loss-free transfer into narrow-neck vessels. Available in extra small (fits microtubes and 5–20 mL flasks) through extra-extra-large (fits 1000 mL+ vessels). Antistatic weighing funnels are single-use; washing removes the antistatic treatment. Reusable funnels needing autoclave sterilization should be standard polypropylene powder funnels, not antistatic weighing funnels.

What you will find:

• Powder funnels with wide stems for smooth solid transfer

• Long-stem funnels for controlled pouring into narrow containers

• Short-stem funnels for faster liquid transfer

• Filter funnels for use with standard filter paper

• Chemical-resistant plastic funnels for lab compatibility

• Disposable funnels for single-use workflows

How to Choose Laboratory Weighing Funnels

Match Size to Flask Neck

The critical specification for a weighing funnel is the stem outer diameter relative to the flask neck inner diameter. Extra small fits 96-well microtubes and 5–20 mL volumetric flasks; small fits 20–50 mL; medium fits 50–200 mL; large fits 200–500 mL; extra large fits 500–1000 mL. A funnel that is too wide will not insert and will spill during transfer—when in doubt, choose one size smaller.

Disposable Antistatic vs. Reusable PP

For analytical weighing of fine powders, use disposable antistatic PP funnels—the antistatic surface dissipates charge that causes powder adhesion. For bulk transfer of coarse materials or liquids where static is not an issue, standard reusable polypropylene powder funnels (autoclavable at 121°C, large-bore stem) are more economical and can be sterilized between uses.

Assorted vs. Individual Packs

Assorted packs covering extra small through extra large provide flexibility when flask sizes vary across experiments and reduce the number of individual SKUs to manage. Individual packs are more economical when only one funnel size is used at high volume.

Flat-Side Stability

All antistatic weighing funnels have one flat side on the funnel body. This flat face allows the funnel to rest stably on a balance pan without rolling during the weighing step before transfer—a design feature absent on standard laboratory funnels.

Compare Laboratory Funnel Formats

Weighing funnel (disposable, antistatic PP) comes in XS to XXL sizes, is antistatic, not autoclavable, and is used for analytical balance weighing and quantitative transfer into volumetric flasks. Powder funnel (reusable PP) is 65–150 mm diameter, not antistatic, autoclavable at 121°C, and used for bulk transfer without balance weighing. Borosilicate glass funnels are chemically resistant, autoclavable, and used for hazardous or aggressive chemicals. Büchner funnels (PP or ceramic) are used for vacuum filtration. Filter funnels (PE/PP) are used for gravity filtration.

Specifications Context

Antistatic polypropylene weighing funnels achieve antistatic performance through a surface additive incorporated during molding; this is a surface treatment rather than a bulk polymer property. The flat side is designed to rest on a balance pan while keeping the stem vertical for direct transfer into volumetric flasks. As of 2026, these funnels are standard in pharmaceutical QC and analytical chemistry labs for gravimetric transfer workflows compliant with USP procedures. Explore weighing dishes and funnels category for related consumables.

Pick the size that fits your work—and everything else gets a lot easier. Contact the MBP Team today.