What is 3D sketching?

Drawing freehand lines that are stored with a position in space rather than as pixels on a sheet. You draw on a plane, move or turn that plane, and the lines stay where you put them when the view rotates.

Do I need to install anything or make an account?

No. The studio runs in the browser and keeps your drawing in that browser, on your device. That also means clearing the browser data can remove it, so export anything you want to keep.

Does it support pen pressure?

Yes, through the browser's Pointer Events: pressure, tilt, the barrel button and the eraser end, where the browser and pen report them. We tested with synthetic pen input in Chromium, not with physical pens yet.

Can I take a sketch into Blender, Krita or Procreate?

Blender gets a script that rebuilds the strokes as curves, tested in Blender 4.5. Krita and GIMP read OpenRaster, and PSD is there for apps that read it. We checked those files with other software, but have not yet opened them in Procreate, Krita, Sketchbook or Clip Studio.

Is it a 3D modelling tool?

No. It makes lines, not solids. It is for working out an idea quickly, before anyone models it.

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Tools & comparisons · 2026-11-01 · 6 min

3D Sketching Online: Draw in 3D Space with a Pen or Finger, in the Browser

A 2D sketch shows one view. Here each line keeps its place in space, so you can turn the idea round and keep drawing from the new side. Turn and draw on the live example, with nothing to install.

Twisting tower with a glowing diagrid and the path of the sun, drawn as 3D lines on a black background

Paper fixes your viewpoint before you start. If the idea needs seeing from the side, you draw it again. In 3D sketching each line keeps its place in space, so you turn the drawing and carry on. Try it below: it is the real engine, not a video.

Turn this tower, then draw on it

It replays line by line. Drag to turn it, press Draw to add your own lines, and try a filter. Nothing you do here is stored.

Twisting tower of glowing 3D lines, ready to replay in the browser

Open in the studio

Key takeaways

Every line stays in 3D: turn the view and it holds its place.
You draw on a plane you can move, so depth stays under control.
Pressure, stabilizer, layers, blend modes and filters are all there.
It runs in the browser, and the drawing stays on your device.

How drawing in 3D stays under control

A pen moves in two dimensions, so something has to supply the third. That something is the drawing plane, and most of the studio's touch design is about making it quick to place.

Pick a plane, or leave it on Auto Ground, front or side are one press away. On Auto, each stroke lands on the plane that faces you most.
Start from a line you already drew A stroke that begins at the end of another line carries the plane to that point, so the next wall grows from the corner.
Turn with two fingers Two fingers either orbit or pinch, never both in one gesture. Home brings you back if you get lost.

Pencil sketch of a pavilion with three saddle-shaped roofs made of straight ruled lines, with columns, setting-out grid and shadow — Three saddle roofs from straight lines, with pencil and a multiply marker layer. Plotted by code in the studio's engine.

The line: what happens between pen and screen

The studio reads pressure and tilt through Pointer Events^[pointer], applies your pressure curve, then steadies the line with a stabilizer of the kind Krita and Clip Studio offer. Hold still at the end of a stroke and it snaps to a straight line, an ellipse or a rectangle. A pen with no pressure sensor, or a finger, uses speed instead.

The 3D sketch studio at tablet size, with tools, plane bar, layers, blend modes and filters beside a drawing of a twisting tower — The real studio at a tablet's size, emulated in Chromium: tools, plane bar, four layers, blend modes and filters.

Layers and filters, without losing the 3D

Each layer has opacity, a blend mode and filters: hue, saturation, brightness, soft edge, grain, glow and duotone. They never touch the lines, so you can change them at any time, and they follow the drawing as it turns.

The same city drawing six times, with the original look and the Blueprint, Wash, Chalk, Neon and Faded filters — One drawing, six looks. Top: no filter, Blueprint, Wash. Bottom: Chalk, Neon, Faded.

Where it fits among 3D sketching tools

This is not a new category: Feather^[feather] is a dedicated 3D sketching app, and Penzil^[penzil] showed the idea in a browser years ago. What sets this one apart is what sits next to it: the same site opens IFC building models, so you can sketch over a real project.

Export	Opens in	Keeps
PNG or a share card	Anywhere, Instagram Stories, LinkedIn	The look, filters included
PSD	Apps that read PSD	Layers, opacity, blend modes, baked filters
OpenRaster (.ora)	Krita, GIMP	Layers, opacity, blend modes, baked filters
SVG	Vector editors	Lines and blend modes, not filters
Blender script (.py)	Blender	Strokes as 3D curves, not filters

What we have and have not tested

We tested the studio in Chromium with synthetic pen and touch input at phone, foldable and tablet sizes. The Blender script ran in Blender 4.5, and the PSD and OpenRaster files were read by other software. We have not yet tried it with physical pens or on physical devices, so gesture thresholds may need adjusting.

References

Feather: free app for drawing in 3D with pen and touch — 80 Level. A 3D sketching app.
Penzil: web-based 3D sketching — CGPress. An earlier browser-based concept sketching tool.
Pointer events — MDN Web Docs. The browser API behind pressure and tilt.

3D Sketching Online: Draw in 3D Space with a Pen or Finger, in the Browser