Looking for feedback on my URL shortener

My url shortener is nothing special, it’s just a functioning url shortener.

I wanted to get feedback on my code. In my previous projects, my code has been inefficient. My calculator worked, but it was an abomination. My focus with this project was clean, efficient code that would work, but also be easy to read. I was inspired by a quote in the FCC newsletter recently -
Anyone can write code that a computer can read, but a good programmer can write code that a human can read.

Please let me know how I can improve the way I write code!