Set these values to 0 for the highest frame rates:
Before touching the config file, ensure the game files are optimized. BEST CONFIG FILE FOR FORTNTE NEW SEASON
Once you've finished editing, remember to right-click , go to Properties , and check Read-only . This prevents Fortnite from overwriting your custom optimizations when you restart the game. Set these values to 0 for the highest
sg.ResolutionQuality=100.000000 (Lower to 80.0 if you have a low-end GPU). remember to right-click