The human development index ranks Tamil Nadu as the 11th most developed state in India. As of the 2011 India census, 72,147,030 people lived in Tamil Nadu.

Of the states in India, Tamil Nadu has a high literacy rate. Literacy rates in the state are 80.33 percent, with 51,837,507 literates.

Tamil is the only official language in Tamil Nadu, while the government of Tamil Nadu has also made English an official language.

Tamil Nadu is home to the second-largest economy in India, with a gross state product (GSDP) of 24.85 lakh crore (US$310 billion) and the 11th-highest GSDP per capita ($2,800) in the world.Statewide poverty decreased from 51.7% in 1983 to 21.1 percent in 2001 Tamil Nadu’s GSDP for the 2014–15 fiscal year was $9.767 trillion (US$120 billion), with a 14.86 percent growth. Next to Maharashtra and Delhi, which together account for 9.12% of all FDI in the nation, it is third in terms of FDI approvals (cumulative 1991–2002), with 225.826 billion rupees ($5,000 million).

The fifth-largest rice producer in India was Tamil Nadu. Tamil Nadu is India’s second-largest exporter of software in terms of value. With 51 percent of all investments, the government is the largest investor in the state. Private Indian investors are second with 29.9 percent, while international private investors are third with 14.9 percent.

Tamil Nadu has six nationalised home banks that began in this state: two government-sector banks, Indian Bank and Indian Overseas Bank, in Chennai; four private-sector banks, City Union Bank in Kumbakonam; Karur Vysya Bank; Lakshmi Vilas Bank in Karur; and Tamilnad Mercantile Bank Limited.

Over a long period of time, a lot of money has been put into the auto industry in Tamil Nadu, which makes heavy vehicles, battle tanks, tractors, railway coaches, motorcycles, tires, and spare parts. Prominent worldwide vehicle companies like BMW, Ford, Robert Bosch, Renault-Nissan, Caterpillar, Hyundai, Mitsubishi Motors, and Michelin, as well as Indian automobile heavyweights including Mahindra & Mahindra, Ashok Leyland, Eicher Motors, Isuzu Motors, TI Cycles, Hindustan Motors, TVS Motors, Irizar-TVS, Royal Enfield, MRF, Apollo Tyres, and TAFE Tractors, have committed 4 billion for constructing a new plant in Tamil Nadu. Daimler AG committed 4 billion for constructing a new plant in Tamil Nadu.

The business of making electronics is growing in Tamil Nadu. Many multinational companies, like Nokia, Flex, Motorola, Sony-Ericsson, Foxconn, Sams, Lenovo, Dell, Sanmina-SCI, Bosch, and Texas Instruments, have chosen Chennai as their South Asian manufacturing base.

Well-known IT companies from all over the world, like Atos Syntel, Infosys, Wipro, HCL Technologies, Tata Consultancy Services, Verizon, Hewlett-Packard Enterprise, Amazon.com, Capgemini, CGI, PayPal, IBM, NTT DATA, Accenture, Ramco Systems, Robert Bosch GmbH, DXC Technology, Cognizant, Tech Mahindra, Virtusa, LTI, Mphasis, Mindtree.