Online whiteboard
A freeform whiteboard in the browser: pen and eraser with adjustable colour and width, undo/redo, clear and PNG export — everything is drawn locally.
Runs in your browserEvery computation happens in your browser — your data never leaves this device.
Canvas
Press and drag with a mouse or finger to draw; switch between pen and eraser at any time.
Brush settings
Drawing happens entirely on a local canvas; nothing is uploaded. Export uses the browser’s native canvas.toBlob.
Status
Strokes: 0 Undo steps: 0 Redo steps: 0 Sample points: 0 The canvas is still blank — press the pointer to start drawing.
What this tool does
- Sketch a diagram, a flow or a quick explanation and export it as a PNG to paste into chat or a document.
- Use it as a doodle pad for kids or a scribble sheet during a call — pen colour and width are adjustable at any time.
- Mistakes do not force a restart: undo and redo step back one stroke at a time, which is far more predictable than guessing at Ctrl+Z.
- When you need a clean asset, clear the board and redraw — the exported PNG always has a solid white background.
Example
Input
Draw a line with the 4px black pen from (40, 40) to (160, 120), then press Undo
Output
Strokes: 0, undo steps: 0, redo steps: 1, the canvas is blank again
One press-and-drag counts as a single stroke, so one undo removes the whole line; redo puts it back exactly as it was.
Frequently asked questions
Is my drawing uploaded or stored on a server?
No. Everything is drawn on a local canvas, the page makes no network requests, and a refresh clears the board. Use Export PNG before you leave if you want to keep the result.
Why does the eraser just paint white?
The board background is solid white, so painting white erases visually and keeps the exported PNG free of transparency. That makes the image easier to drop into white documents.
How many undo steps are available?
Up to 100 snapshots are kept, so you can undo 100 times in a row. Each stroke counts as one step, clearing the board counts as one step, and the oldest snapshot is dropped once the cap is reached.
Does it work on a phone?
Yes. The canvas uses pointerdown / pointermove / pointerup, so touch and stylus input share one code path, and touch-action: none keeps the page from scrolling while you draw.
What resolution is the exported PNG?
The canvas is a fixed 960 × 540 pixels and does not follow the window size. On narrow screens it is scaled down for display while the internal coordinate system stays 960 × 540.
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