FEN to URL

This may be super-trivial, but the only way I've figured out how to quickly convert a FEN to a playable URL is to start with the position, click "play from position", then retrieve the penultimate URL from browser history since there's a redirect for some reason.

For example, a simple pawn vs king endgame shows the encoding is trivial (you can almost read the position straight from the URL -- %2F separates the files):

https://www.chess.com/practice/custom?color=white&fen=6k1%2F8%2F8%2F8%2F8%2F3P4%2F8%2F3K4+w+-+-+0+1&is960=false&moveList=

Here is an example of a game encoding. The FEN is encoded first, followed by a move list. BTW, this is an interesting position from my latest blitz game where I blundered M1.
https://www.chess.com/practice/custom?color=white&fen=rnbqkbnr%2Fpppppppp%2F8%2F8%2F8%2F8%2FPPPPPPPP%2FRNBQKBNR+w+KQkq+-+0+1&is960=false&moveList=e2e4+e7e5+g1f3+b8c6+c2c3+g8f6+d2d4+f6e4+d4d5+c6e7+f3e5+d7d6+f1b5+c7c6+d5c6+d8b6+c6b7+e8d8