VASPKIT

Basic features:

1. Generate KPOINTS, POTCAR and INCAR for a given POSCAR file;
2. Elastic-constants using stress-strain or energy-strain methods;
3. Equation-of-state fitting;
4. Suggested k-paths for a given crystal structure;
5. Optical adsorption coefficient;
6. Band structure unfolding;
7. Fermi surface;
8. Density-of-states and band-structure;
9. Charge/spin density, Charge density difference;
10. Vacuum level and work function;
11. Wave-function analysis;
12. Molecular-dynamics analysis;
13. Effective mass of carrier;
14. Symmetry finding and operations;
15. 3D band structures;

More details can be found in its official website https://vaspkit.com.