its navy predecessor the F/A-18 has a range of supposedly 1,275 miles, ‘clean’. i would not expect the nextgen fighter to have better legs. efficiency usually gets worse with each generation, just like the accompanying federal bureaucracy.
The F-35C, which is the successor to the F/A-18, has an unrefuelled range of 1,400 NM on internal fuel.
The F-35B, reported on in this post, is the successor to the AV-8B, which has an unrefuelled range of 900 NM on internal fuel, and a ferry range of 1,800 NM with external tanks.
I cannot find specs for the F-35A/B/C ferry range which would include external fuel tanks.