There's two ways (one which you mentioned): - Use a ResizeObserver and observe a wrapper element, then resize and redraw your canvas when it notifies you. http

There's two ways (one which you mentioned): - Use a ResizeObserver and observe a wrapper element, then resize and redraw your canvas when it notifies you. https://developer.mozilla.org/en-US/docs/Web/API/ResizeObserver https://developer.mozilla.org/en-US/docs/Web/API/ResizeObser... - Use a Paint Worklet. It hooks directly into the browser painting system, but has some limitations on what you can draw with the canvas today. https://developer.mozilla.org/en-US/docs/Web/API/PaintWorklet https://developer.mozilla.org/en-US/docs/Web/API/PaintWorkle... You could also consider SVG instead of Canvas. There's no way to automatically resize and replay draw commands but scaled up like you're asking though.