Turnover for F&O trading is generally calculated using the sum of absolute values of profits and losses across all trades, not simply netted against each other. This means an active trader can have substantial turnover even with a comparatively modest net profit, since every trade’s result — win or loss — contributes to turnover in absolute terms.
Related Reading
See a full worked calculation and why it matters for audit thresholds in Turnover, Tax Audit, and ITR Filing for F&O Traders.