Short answer: paste the markup or open the file, set the pixel width and download. The height follows the SVG's own aspect ratio, so nothing gets squashed, and a script inside the file cannot run because rendering goes through an image element.
Vector in, pixels out — once
Export at the largest size you will ever need. Upscaling a PNG later adds blur, while a larger SVG render costs only bytes. For a favicon set, the favicon generator renders every size from one source instead.
Fonts and remote assets
Text in an SVG renders with whatever font the browser has, unless the text is outlined. A remote image or stylesheet inside the file will not load, so the PNG can differ from what a design tool showed — that is the same sandbox that makes the rendering safe.