Your STL in.
A printable mold
frame out.
FORMA LABS designs the 3D-printable casting frame around your model — contoured walls, seams, clips, register keys, a pour funnel and core rods. Print it, pour silicone or plaster, cast copies.
From model to mold in one evening
Everything runs in your browser. No CAD, no booleans, no measuring — FORMA LABS does the geometry.
1Load & check your model
Drop in an STL. FORMA LABS checks the mesh and, if it has holes, flipped faces or overlapping parts, repairs it and merges it into one solid.
2Pick the mold
Single pour or 2–6 pieces, contoured shell, rectangular box or offset shell — for silicone or plaster. Check undercuts in one click.
3Tune the details
Mold thickness, clips, seam keys, pour funnel, a support sleeve for tall molds and fluted core rods for bores — all live in 3D.
4Print, pour, cast
Export each printable part as STL. The Cast mold view shows the silicone you will get, and Estimates tell you how much to mix.
Made by a mold maker, for mold makers
Contoured shells
Frames that hug the shape of your object, so you mix far less silicone than with a square box.
Multi-piece & slip casting
Split into 2–6 side pieces plus a base, with register keys, a slip reservoir and plaster-ready shallow keys.
Happy STL repair
Closes holes, turns flipped faces, removes paper-thin double walls and unions overlapping parts into one clean solid.
Pour funnel & cores
A funnel former that casts the pour hole and reservoir, and core formers for through-holes.
Core rods & sleeves
Fluted stiffener rods keep tall bores straight; a loose support sleeve keeps thin silicone molds standing while you pour.
Cast mold preview
See the silicone you will pour, flipped open-side up, and slide it apart piece by piece before you print anything.
Clips, keys & tolerances
Snap clips, seam ribs, skirts and a rimmed base plate — sized with a fit tolerance so printed parts actually fit.
Undercut check
Paints the model red where a rigid piece would lock and amber where silicone will still stretch free.
STL export
Every frame part as its own STL, or all parts nested on one plate. Your models never leave your computer.
One plan. Everything included.
- Every mold style, piece count and material
- Happy STL mesh repair & boolean merge
- Sleeves, core rods, funnels, clips & keys
- Unlimited molds and STL exports
- New features as they ship
- Sign in with your e-mail. No password — we send you a link and a code.
- Add a card at checkout. Nothing is charged today; Lemon Squeezy handles payment and tax.
- Use everything for 14 days. Make as many molds as you like. We e-mail you two days before the trial ends.
- Keep it or cancel. Cancel before day 14 and you pay nothing. Otherwise it continues at €3.99/month.
Good to know
What do I need?
An STL of the object you want to copy, a 3D printer for the frame parts (PLA or PETG is fine), and mold material — silicone, or plaster for slip casting and press molds. FORMA LABS runs in any modern browser on a desktop or laptop.
Do my models get uploaded?
No. Your STL is opened and processed entirely in your browser. Nothing about your models is sent to us.
Silicone or plaster?
Both. Silicone is flexible and forgives small undercuts, so single-pour molds work for many shapes. Plaster is rigid, so FORMA LABS builds multi-piece molds where every piece pulls straight off, with shallow keys and a slip reservoir.
My STL has holes or is made of several parts. Will it work?
Usually, yes. FORMA LABS checks every model when it loads. If it needs repair, one click closes holes, fixes flipped faces, removes zero-thickness walls and merges overlapping parts into one solid — and you can download the repaired STL.
Why do I need a card for the trial?
So your work isn't interrupted when the trial ends. Nothing is charged during the trial, we e-mail you a reminder two days before it ends, and cancelling takes two clicks from your account page.
How do I cancel?
Account → Manage billing → Cancel subscription. You keep access until the end of the period you paid for (or the end of your trial).
Can I use it on several computers?
Yes — sign in with the same e-mail on each. An account is for one person.
Do you offer refunds or invoices with VAT?
Lemon Squeezy is our reseller, so receipts and VAT invoices come from them and can be downloaded in Manage billing. See the terms for refunds.
Ready to make your first mold?
14 days free, then €3.99/month. Cancel any time.