Slippage needs two prices, and most journals store one
Intended price minus filled price, signed by side. Without the first number there is nothing to measure.
Traders talk about slippage constantly and record it almost never, because the broker file only knows where the trade actually happened.
The intended price lives in your head until you type it somewhere.
Capture intent, then measure
One extra field at order time. After a month, the distribution tells you whether your fills are usually fine with occasional shocks, or quietly worse every single time.
Rupees of premium per unit versus the intended price. Two outliers were entries into a fast move. Illustrative journal data, not a live book and not a performance claim.
Name the cause while you remember it
Thin strike, fast move, freeze, or a fat-fingered order type. Four labels cover most cases, and they separate market conditions from your own execution choices.
Be careful with conclusions about brokers
Persistent slippage may be your order type, your strike selection, or the time of day. A journal should show the pattern, not manufacture claims about execution quality — that is a research exercise with a much higher evidence bar.
- Thin strike or wide spread at the moment of the order
- Fast move, price gone before the order arrived
- Freeze or circuit, no fill available
- Order type: market where a limit was intended
Key takeaways
- Log an intended price or slippage cannot be measured.
- Label the cause: liquidity, speed, freeze or order type.
- Report rupees and percentage; on cheap premium they tell different stories.
Not advice, not a call. NiyataBook is a personal trading journal, not a SEBI-registered investment adviser or research analyst. Everything above looks backwards at trades that already closed. What happened in a book does not promise what happens next, and F&O can take a year’s savings in a week.