Free Parametric Funnel Generator — Custom STL Funnels for 3D Printing

Need a funnel in a specific size for your workshop, kitchen or lab? The TekOnline Funnel Generator lets you create a custom funnel in your browser, preview it in 3D and download a ready-to-print STL — free.

Open the Funnel Generator

Why a parametric funnel generator?

Hardware store funnels come in limited sizes. A 3D printed funnel gives you the exact dimensions you need — whether it is a tiny funnel for filling small bottles, a wide-mouth funnel for workshop fluids or a long-spout funnel for hard-to-reach fill ports.

Funnel generator parameters

• Top Diameter: 20 mm to 500 mm — the wide opening at the top
• Spout Outer Diameter: 4 mm to 100 mm — the narrow outlet
• Spout Inner Diameter: 2 mm to 98 mm — the flow channel diameter
• Wall Thickness: 0.4 mm to 10 mm — thicker for durability, thinner for speed
• Spout Length: 10 mm to 200 mm — how far the spout extends
• Total Height: 20 mm to 400 mm — overall funnel height

Anti-suction ribs

The funnel generator includes an optional Anti-Suction Ribs toggle. When enabled, vertical ribs are printed on the outside of the spout to prevent the funnel from forming a vacuum seal against the container you are filling. This is especially useful for:

• Filling bottles or jerry cans where the spout fits tightly into the neck
• Pouring viscous liquids like oil, detergent or resin
• Any setup where smooth, uninterrupted flow matters

Funnel presets

Three quick-start presets cover common use cases:

• Standard 80 mm: 80 mm top, 12 mm spout, 80 mm height — general workshop funnel
• Large 120 mm: 120 mm top, 20 mm spout, 120 mm height — for bulk pouring
• Mini 40 mm: 40 mm top, 8 mm spout, 50 mm height — for small bottles and precision work

Printing tips for funnels

• Use PETG or PP for funnels that will contact oils, fuels or solvents — PLA degrades
• Print with 3+ wall loops to ensure the funnel is watertight
• Enable ironing on the inside surface for a smoother flow path
• For food-grade use, print in a food-safe filament and coat with food-grade epoxy resin

How to generate a custom funnel STL

1. Open the Parametric 3D Generator
2. Select Funnel from the generator dropdown
3. Set top diameter, spout dimensions, wall thickness and height
4. Enable anti-suction ribs if needed
5. Click Generate Preview to see the 3D model
6. Download the STL and open in your slicer

Generate a custom funnel STL now — free, no account required