CTC (Cost to Company) is everything the employer spends on you — including money you never see monthly: the employer's PF contribution, gratuity provision, insurance premiums and one-time bonuses. Your in-hand salary is what remains after those are set aside and after your own deductions: employee PF (12% of basic), professional tax, and income tax (TDS).
The biggest lever is the basic-salary percentage: PF and gratuity are both computed on basic, so a structure with 50% basic gives more retirement savings but less monthly cash than one with 35% basic on the same CTC. When comparing two offers, compare estimated in-hand — not CTC — and use this alongside our application guides and job tracker while you interview.