What does the P&L preview calculate from?
Four things you type — entry, exit, contracts and fees — multiplied by what one point of that instrument is worth. A blank preview is not a bug. Either the trade has no exit price yet, or the instrument has never been told what a point is worth — and in the second case the form would rather show you nothing than a confident wrong number.
The line reads Computed P&L and updates as you type. The arithmetic is short:
- The distance in your favour. Long is exit minus entry, short is entry minus exit — so a profitable short shows a positive figure.
- × what one point is worth, taken from the instrument's entry in your Asset Registry.
- × contracts, which is 1 unless you say otherwise.
- − fees, which is 0 unless you fill them in.
What a point is worth depends on the asset class, and this is the part that surprises people coming from a futures-only journal:
- FuturesTick value divided by tick size. An NQ tick of 0.25 worth $5 makes one point worth $20.
- Shares, crypto and FXOne dollar per point unless the instrument carries a multiplier of its own. One share moving $1 is $1.
- OptionsThe contract multiplier, usually 100, and there is no fallback here. An options contract with no multiplier recorded produces no preview at all, because guessing 1 would book a $1.20 premium as $1.20 instead of $120.
Figures are rounded to whole dollars, except options, which keep the cents — on a $0.30 premium the cents are most of the trade.
When the preview stays blank, it is one of two things:
Step by step
- Entry or exit is not filled in yet. A trade you are logging at entry has no exit, so there is no distance to price. This is normal; the preview appears when you close it.
- The instrument cannot say what a point is worth. Futures missing their tick economics, or an option with no multiplier. Fix it once in the Asset Registry — tick size, tick value and multiplier all save from there — and the preview starts working for every future trade on that instrument.
You can always overrule it. The field is labelled Net P&L (override) and sits in the main body of the form, just after the account — not hidden behind More details. Its placeholder shows you the computed figure as auto: $…, so you can see what the form worked out before deciding to replace it. Type a number there and yours is what gets saved, which is the escape hatch for a fill your broker priced differently.