Rollpie Pen is a free SVG path editor that runs in your browser with no install. With the pen tool, click on the canvas to drop an anchor, and drag to make a Bezier curve. Press Enter to finish the path, then switch to the move, direct-select, or add-point tools to adjust nodes and handles.
Set stroke color, width, dashes, fill, and opacity in the panels on the right, and manage paths as layers and groups in the scene tree. Zoom with the mouse wheel, hold Space and drag to pan, and press Ctrl+Z to undo. Copy or save your paths as SVG or path data from the menu, and save and load your work as a project.