Position sizing from your closed book, not from hope
Two lots means nothing on its own. Here is how to read the rupees you actually risked, trade by trade.
Ask a trader how big their last trade was and you will hear a lot count. "Two lots." It sounds modest. It tells you nothing.
Two lots of an index future and two lots of a ₹12 option are not the same bet, not the same margin, and definitely not the same bad day. Size only becomes real when it is expressed in rupees you could lose.
Convert every trade into one number
For a directional trade, rupees at risk is roughly the distance to your stop multiplied by quantity. For a long option, the honest worst case is close to the premium you paid plus charges. For a short option, there is no neat cap, which is exactly why it deserves its own field.
Do this once for a quarter of trades and something uncomfortable usually appears: the number moves around far more than you remember. Most books do not have a size. They have a mood.
Lots are packaging. Rupees at risk are the product.
Median risk sits near ₹4,200. Three sessions ran 2–3.5x that. Illustrative journal data, not a live book and not a performance claim.
Then look at where the big ones landed
Sort the same quarter by rupees risked and glance at the outcome column. In a lot of retail books the fattest risk clusters right after a loss, or right after a run of wins. Both are size decisions made by feeling rather than by plan.
This is not a prediction that the next oversized trade will fail. It is a description of where your outliers have been sitting. Description is the entire job of a journal.
Write the cap before the bell
One line on the morning card is enough: the maximum rupees you are willing to lose on a single idea today. After the close, compare.
If the number never existed, you cannot grade the day, you can only narrate it. And narration is where every trader is undefeated.
- Planned risk in rupees, written before the first fill
- Actual quantity and contract spec on the day of the trade
- Worst unrealised move against you while the trade was open
- A size-up flag when quantity crosses your own 20-day median
Key takeaways
- Express size in rupees at risk, not lots.
- Compare each trade to your own median, not to someone else’s screenshot.
- A cap written before 9:15 is a rule. The same number typed at 3:45 is a memoir.
Where these numbers come from
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.