Parametric CAD is 3D modeling driven by editable parameters and a recorded history of operations, so changing a dimension rebuilds the whole model.
Parametric CAD is a way of 3D modeling where the design is driven by editable parameters (dimensions, constraints, and a recorded history of operations), so changing a value rebuilds the model automatically. Instead of pushing vertices around a static mesh, you define a box as “40 mm wide” or a hole as “6 mm from the edge,” and every downstream feature updates when you edit that number.
Parametric CAD models a recipe, not a static shape. Here is what that means in practice.
Every operation — sketch, extrude, boolean, fillet — is recorded on a timeline you can reopen and change; the model rebuilds downstream.
Type exact lengths and angles and add constraints. A part is defined by its numbers, not by where you happened to drop a vertex.
Edit a driving parameter and the whole model updates, which is why parametric CAD is so good for parts that must fit together.
Historically this meant an installed desktop package and a licence to go with it. OwlCAD runs the same parametric model in a browser tab: the kernel is compiled to WebAssembly and evaluates on your own machine, so there is nothing to install, it works the same on Windows, macOS, Linux and ChromeOS, and a part starts in seconds rather than after a download.
Sketch a shape, set a dimension, then change it. OwlCAD rebuilds the model live, free in your browser.
Mesh modeling edits fixed triangles (an STL), and direct modeling pushes and pulls faces without a recorded recipe. Parametric CAD keeps an editable history of operations and the dimensions that drive them, so you can reopen an early sketch or boolean, change a number, and the rest of the model rebuilds. That makes design changes fast and precise — ideal for parts that must fit together.
Yes. OwlCAD is browser-based parametric CAD: primitives, sketches, extrude and revolve, booleans, and fillets or chamfers all live on an editable history timeline you can scrub and retro-edit, and everything works in true millimetres. Change a dimension and the model rebuilds downstream.
No. Some parametric tools are script-based, but OwlCAD is fully visual: you sketch, set dimensions and combine shapes directly, and can expose chosen parameters as sliders for others to customize. No programming required.
Prints often need dimensional tweaks: a tolerance for a snap fit, a wall thickness, a bracket length. With parametric CAD you edit the driving dimension and the model updates exactly, then you export a print-ready STL or 3MF. OwlCAD layers print checks — watertightness, wall thickness, and overhangs — on top of the parametric core.