STCG, short-term capital gains, is the profit on listed equity shares, equity ETFs or equity mutual funds held for twelve months or less before selling. It is taxed at a flat rate regardless of your income slab; at the time of writing the rate is 20%, raised from 15% in 2024, so check the current figure. Suppose you buy 50 SBI shares at ₹760 for delivery and sell them four months later at ₹820. The gain is ₹3,000 and the tax is ₹600. Short-term losses can be set off against both short-term and long-term gains and carried forward for eight years if you file your return on time. Note that intraday profits are not capital gains at all; they are speculative business income taxed at slab rates, and F&O profits are non-speculative business income. Keep your contract notes and use the broker's tax report.