example.com/[a-zA-Z0-9] the code can be any mix of numbers + uppercase/lowercase letters and it's 5 characters. How long would it take to brute force or is there an easier/faster way to do it?
This wont take much long but as mention by @steffen it depends on the server response if your server is responding fast then i could suggest with gobuster it will take maximum five hours with all possible combination. use atleast 50 threads.
gobuster -u https://examplecom -w your-wordlist -t 50
generate the combination first and then give it to go buster it will complete with five hours.