Files Import and Export

The .whittle format

A ZIP file containing:

Entry	Content
manifest.json	Format and schema version
document.json	The full design: parameters, features, body metadata, rollback position, timestamps
thumbnail.png	256 px preview image

The format is plain JSON, open and readable. Older files are migrated automatically; files from a newer version are refused with a clear message instead of being misread. Imported STEP/STL files are embedded in the design, so a .whittle file is self-contained.

Saving and opening

• Save (Ctrl+S) and Save as (Ctrl+Shift+S) use the system file dialog where the browser supports it (Chrome, Edge, the desktop app); otherwise they download the file.
• Open with Ctrl+O, or drag and drop a .whittle file onto the window.
• Autosave: the design is saved in the browser about a second after every change. After a crash, the start screen offers Continue where you left off.
• Closing with unsaved changes asks for confirmation.
• Desktop app: double-clicking a .whittle file opens it.
• Version history (Export ▸ Version history, or Ctrl+K "history"): every save keeps the previous version, on your computer (desktop app), in the browser (web), or on the server (self-hosted). Restore one, or open it as a copy.
• Self-hosted server: Save stores the design in your library on the server; if it was saved elsewhere in the meantime, you're asked before anything is overwritten.

Export

Format	Use	Notes
3MF	Slicers (Bambu Studio, PrusaSlicer, OrcaSlicer, Cura)	Recommended for 3D printing; units included
STL	Any slicer or mesh tool	Binary
STEP	Other CAD (Fusion 360, SolidWorks, Onshape, FreeCAD), CNC and manufacturing	Exact geometry
SVG	One sketch, for laser and vinyl cutters, plotters, Inkscape, Illustrator	True size, in millimetres
DXF	One sketch, for laser cutters, CNC and CAM, AutoCAD	Units set to millimetres
PNG	Pictures	Save image

Import

Format	How	Notes
STEP (.step, .stp)	Create ▸ Import, or drag and drop	Exact geometry, becomes a body
STL	Same	Triangles are sewn into a solid and flat areas are merged into clean faces. Limit: 40,000 triangles
SVG	In a sketch: Special ▸ Import SVG	Closed paths become editable sketch outlines; you choose the width

Files up to 40 MB. Each import has a Scale field.