How do I add more ram to my forge server?

[ToxicSamurai]

I have a .bat that has this text:

java -Xmx4G -Xms1G -jar minecraft_server.1.12.2.jar nogui
PAUSE

and whenever I try to launch the server through the .bat it gives this error:

Invalid maximum heap size: -Xmx4G
The specified size exceeds the maximum representable size.
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

I'm on windows 10 trying to make a modded 1.12.2 server using forge 1.12.2-14.23.5.2852.

Thanks!