A car's resale value is decided long before you sell it — by the brand, the variant, the colour, the number of owners and how honestly you kept the service record. This tool estimates what your car is worth today from those inputs, using depreciation curves and the resale trend for that brand in India.
The estimate is a range, not a promise. Dealers price in their own margin, and a private sale usually gets 5-10% more than a trade-in. Use the range as the number to negotiate around, and check the service history before you quote a figure.