iOS 12.3 - iOS 13.4.1 - Checkra1n Jailbreak
Download Checkra1n from official site.
Drag and Drop Checkra1n DMG file to run.
Now open Checkra1n.
Now connect your Device to PC.
Tap Start Button.
Tap Next button to enter DFU mode.
Now put your Device to DFU mode. Just follow on-screen instructions to put your Device to DFU mode.
You will have Checkra1n app once your Device booted.
Now check your Device for Checkra1n app.
Now tap Checkra1n app to open the Checkra1n app.
Now, you will have Cydia name on Checkra1n main interface and tap on it.
Now, you can see Cydia Downloading.
Once all processes done, you will have Cydia application on your Device.