Put the numbers in the link
Every parameter is a link parameter; the link below opens the example part. ChatGPT, Claude or any assistant can write one like it from the parameter list (names, units, ranges) at: parameter list (JSON)
Parametric box generator: exact inside size, hinged, snap, lip or sliding lid
Enter the inside dimensions of what you need to store and pick a lid: a hinged lid that comes off the printer already assembled, a snap-on or drop-over lid, a lid that slides along dovetail rails, or none. The box rebuilds live as real CAD — anything the options miss, like dividers or a label slot, is one AI edit away.
Use it right here
The real generator runs in your browser: set the parameters, then download STEP or STL. Nothing to install, no sign-up.
The first open downloads the CAD engine (about 20 MB).
- - Dimensions are the inside — size it to the thing, not the print
- - Hinged lid with a print-in-place hinge, or a separate pin
- - Clip, toolbox clasp or magnet latch on the hinged lid
- - Dividers, a label slot, a cable notch? Press “AI edit” and say it
Parameters you can tune
Each parameter below rebuilds real geometry on every change — this is parametric CAD, not a scaled mesh.
| Parameter | Default | Range | What it does |
|---|---|---|---|
| Inner lengthINNER_L | 80 mm | 25 – 250 | Interior length — size it to what goes inside. |
| Inner widthINNER_W | 50 mm | 25 – 250 | Interior width. |
| Inner heightINNER_H | 30 mm | 16 – 150 | Interior height of the box, floor to rim. |
| Wall thicknessWALL | 2.4 mm | 2 – 4 | 2.4 mm is about six perimeters with a 0.4 mm nozzle. |
| Lid typeLID | hinged | hinged / snap / lip / sliding / none | A hinged lid, a snap-on lid, a lid that drops over a lip, one that slides along dovetail rails, or none. |
| HingeHINGE | print-in-place | print-in-place / pin | Hinged lid only: printed already assembled, or with a separate pin. |
| LatchLATCH | clip | clip / toolbox / magnet / none | Hinged lid only: a snap clip, toolbox-style clasps, magnets, or none. |
| Hinged lid depthLID_DEPTH | 10 mm | 4 – 40 | Hinged lid only: how deep the lid is. |
| Corner radiusCORNER_R | 4 mm | 0 – 12 | Outside corner rounding (the sliding lid keeps square corners so it can slide out). |
Every parameter can go in the page's link, so one link opens exactly the part you want. Example (120 × 80 × 40 mm inside, sliding lid):https://www.forgent3d.com/en/generators/parametric-box-generator?INNER_L=120&INNER_W=80&INNER_H=40&LID=sliding
What's in the STEP file
- - Box and lid export as separate solids in one file — 101 exact faces for the default hinged box, the rounded corners and the hinge knuckles as true cylinders.
- - Open it in CAD to put a logo, a cable notch or mounting holes exactly where they belong, or hand it to a print service that wants STEP.
STEP AP214 in millimetres, exact B-rep — it opens directly in SolidWorks, Fusion, FreeCAD, Onshape or Inventor, and goes straight into a CNC quote form. STL for the slicer is one click too.
How it compares
| This generator | Typical online STL generator | Vendor CAD library | |
|---|---|---|---|
| Any size within the range | Yes | Yes | Catalog sizes only |
| STEP with exact surfaces | Yes | Usually an STL mesh only | Yes |
| Changes the sliders don't cover | “AI edit” on the page | No | No |
| Account needed to download | No | Usually no | Often |
Let AI change it
Edit with AI on the page
Press “AI edit” in the generator and say what to change — a keyway, holes, a different shape. The AI edits the part's model.py and it rebuilds in your browser, with undo. A few edits a day are free without signing in; to keep the result or go further, copy it into your models and continue with the AI agent.
Edit with AI →Keep going in your workspace
For bigger changes, several rounds, or a part you want to keep: copy it into your models (free account). The Forgent3D AI agent reads the model.py, edits it, rebuilds it and checks the result itself.
Copy and continue with the AI agent →How it works
- 1.Open the generator — the model builds right in your browser, nothing to install.
- 2.Tune dimensions and options in the parameter panel; the geometry rebuilds live in 3D.
- 3.Export STL / STEP for printing — or ask the AI agent for features beyond the sliders.
FAQ
Which lid should I pick?
The hinged lid with the print-in-place hinge for a box you open often — it comes off the printer assembled. Snap-on for a lid that must stay shut when the box is carried, the lip lid for a dust cover you lift off, the sliding lid for a pencil-box feel (it keeps square corners so it can slide out), and none for an open tray.
How thick should the walls be?
The default 2.4 mm is about six perimeters with a 0.4 mm nozzle — stiff enough for everyday storage. Go to 3–4 mm for boxes that get carried full or screwed to a wall.
How do I make a 120 × 80 × 40 mm box with a sliding lid?
https://www.forgent3d.com/en/generators/parametric-box-generator?INNER_L=120&INNER_W=80&INNER_H=40&LID=sliding — the sizes are the inside of the box. Download STL to print box and lid, or STEP to edit.
Can I add dividers or a label slot?
Yes: press “AI edit” in the generator and say it (“two dividers across the width”, “a label slot on the front”). The AI edits the box’s model.py on the page; copy it into your models to keep it and to continue with the AI agent.
Can I sell prints made with these generators?
Yes. Models you generate and the STL / STEP files you export are yours: print them, sell the prints, or use them in a product. No attribution to Forgent3D is required.
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Already have your own .scad file? Convert OpenSCAD to STEP → · Preview it in the browser →