Contract size is three different numbers
“How big is one contract?” has three answers, and mixing them up is how traders end up surprised by a loss. Tick value is what the smallest price increment is worth. Point value is what a full point is worth — the contract's multiplier. Notional value is the face value the contract actually controls, which is almost always far larger than the margin you posted to trade it.
Tick value = Tick size × Point multiplier
Notional value = Price × Point multiplier
One MNQ at 20,000 costs a few hundred dollars in day-trading margin but controls $40,000 of Nasdaq-100 exposure. That gap is the whole reason futures cut both ways, and it's the number the calculator above puts in front of you.
“Lot size” in futures
If you came from forex, lot size means contract count here — futures have no standard/mini/micro lot convention layered on top of the instrument. The instrument itself is the size: MNQ is the micro version of NQ, at one tenth the multiplier. So “what lot size should I trade?” becomes two separate questions: which contract, and how many of them. This page answers the first; the position size calculator answers the second from your account risk.
The fees nobody puts in the calculator
Exchange, clearing and NFA fees are charged by the venue, not your broker, so they're identical wherever you route the order — and they usually don't appear in your broker's fee column at all. On a micro contract they're a meaningful share of the cost of a scalp. Where we've verified a product's rates against a real broker ledger, the calculator shows them; where we haven't, it says so rather than showing $0.00 and understating your cost.