Futures move a contract, not a share, and the contract carries a multiplier that the naked price never shows. Buy one contract at 50,000 with a multiplier of one and you control 50,000 of exposure; give the same contract a multiplier of 50 at the same price, the same direction, and the same margin percent, and the exposure is 2,500,000. The Futures Contract Calculator runs in the browser and uploads nothing: the underlying price, the multiplier, the margin percent, the leverage, the contract count, the direction, and an optional exit price go in, and the page returns the contract value, the required margin, the P and L once an exit price is present, and a scenario table. The position data never leaves the tab.
This post walks the four numbers a real entry decision needs, in order: the 50,000 default contract at 10 percent margin, what a 1, 5, and 10 percent move does to it, where the stop comes from, the difference between the margin input and the leverage input, the funding cost on a perpetual, and how the margin becomes a stake with a risk number attached.
How the Futures Contract Calculator Works: four inputs, four outputs
The contract value is price times multiplier times contract count. At the defaults, 50,000 times 1 times 1, the value is 50,000. The required margin is a fraction of that value set by the margin percent input: at 10 percent it is 5,000, at 5 percent 2,500, at 20 percent 10,000. The P and L appears only when an exit price is present, and it is the price difference times the multiplier times the contract count, positive for a long when the exit sits above the entry and for a short when it sits below. The return on margin divides that P and L by the required margin, and the scenario table repeats the same division on every row.
One structural fact drives the whole table: the return on margin depends on the percent the price moves and the margin percent, and on nothing else. The multiplier and the price scale the dollars, not the percent. At 10 percent margin, a 1 percent move is 10 percent on margin, a 5 percent move is 50 percent, and a 10 percent move is 100 percent, which is the entire posted margin. The same 1 percent move is 20 percent at 5 percent margin and 5 percent at 20 percent margin. Before the entry, the size of one R is a decision, and the Risk/Reward Ratio Calculator is where that decision gets written down: the stop distance is the risk, the target distance is the reward, and the ratio is the price of the trade before a single contract is bought.
The Standard Case: a 50,000 Contract at 10 Percent Margin
Run the defaults: price 50,000, multiplier 1, margin 10 percent, leverage 10, one long contract, no exit price. The contract value is 50,000 and the required margin is 5,000. The scenario table has six rows. A 1 percent move takes the price to 50,500 or 49,500, the P and L is 500 either way, and the return on margin is 10 percent. A 5 percent move reaches 52,500 or 47,500, the P and L is 2,500, and the return on margin is 50 percent. A 10 percent move reaches 55,000 or 45,000, the P and L is 5,000, and the return on margin is 100 percent: the full margin, on either side of the entry.
Add an exit price and the P and L becomes a settled number instead of a range. A long entered at 50,000 and exited at 52,000 shows a profit of 2,000 and a return on margin of 40 percent. Exited at 45,000 it shows a loss of 5,000 and a return of minus 100 percent, the entire posted margin. The short side mirrors the same rows: a short entered at 50,000 and exited at 48,000 shows the same 2,000 and the same 40 percent, because the price difference flips sign with the direction. The exit price is where the scenario table stops being hypothetical.
The stop is the part of the entry that turns the 1 and 5 percent rows into dollars you are willing to lose. A fixed stop two percent below entry on this contract is 1,000, which is 20 percent of the 5,000 margin. The Stop Loss / Take Profit Calculator takes the entry, the stop, and the target, and returns the risk in dollars, the reward in dollars, and the ratio between them, so a 1,000 risk against a 2,000 target is a 2 to 1 trade before the position is opened.
Where the Stop Comes From: fixed points and ATR
A fixed stop is a choice in price distance: two percent below entry here is 1,000 per contract no matter how the underlying behaves that day. It is simple, and it is wrong on the two days that matter. On a high-volatility day two percent is a routine tick, and on a quiet day two percent is a week of range. The distance should come from the instrument, not from a preference.
ATR is the standard source. It measures the average true range over a lookback window, and a stop at one or two times ATR below entry places the stop where the normal noise of the instrument ends. The ATR Stop Loss Calculator takes the high, low, and close series, computes the period ATR, and returns the stop price and the stop distance in points. On this 50,000 contract with a multiplier of 1, a stop 500 points away is 500 per contract, 10 percent of the margin, and the ATR decides whether 500 points is one bar of noise or ten.
Margin and Leverage: Two Different Numbers
The tool keeps the two concepts separate, and the separation is worth keeping. The margin percent input is what computes the required margin: 10 percent of 50,000 is 5,000, and that is the stake the tool divides the P and L by. The leverage input, 10 by default, does not enter the margin calculation at all; it selects which row of the comparison table is highlighted, and it is echoed back as the leverage effect. The comparison table does its own math, and its margin is the contract value divided by the leverage: for 2, 3, 5, 10, 20, 25, and 50 times, that is 25,000, 16,667, 10,000, 5,000, 2,500, 2,000, and 1,000.
Every row of that table prices the same 10 percent move, worth 5,000 of P and L on this contract. At 2 times the return on margin is 20 percent, at 3 times 30 percent, at 5 times 50 percent, at 10 times 100 percent, at 20 times 200 percent, at 25 times 250 percent, and at 50 times 500 percent, on the way up and on the way down in equal measure. The table is the honest version of the leverage advertisement: the gain and the loss share the same row, and the row that matches your margin percent is the one to read. The table stops at 50 times, and the honest extension is that at some row the margin becomes smaller than the smallest adverse move that actually happens, which is the liquidation condition.
Where that condition sits, exactly, depends on the maintenance margin and the fee structure, and the Liquidation Price calculator solves for it: given the entry, the leverage, and the maintenance margin, it returns the price at which the position is closed out, and the distance from entry to that price is the true stop of the account, not the one you chose. On a 10 times position entered at 50,000 that price sits roughly 5,000 away, which is the same 10 percent the table already priced as a 100 percent loss of the margin.
Perpetual Futures: the Funding Rate You Keep Paying
Deliverable futures expire and settle; perpetuals do not, and the mechanism that keeps a perpetual pinned to the spot is the funding rate, charged between longs and shorts at fixed intervals, usually every eight hours. The rate is a cost or an income on the notional, and it accrues for as long as the position is held, on every holding day, whether the price moves or not.
On this 50,000 contract, a rate of 0.01 percent per eight hours is 5 per interval, 15 per day, and 5,475 per year, which is 10.95 percent of the notional and 109.5 percent of the 5,000 margin. A position that trades sideways for a year at that rate loses its entire posted margin in funding before the price table above is ever consulted. The Funding Rate calculator takes the rate, the interval, and the notional, and returns the holding cost annualized, so the number to compare against the expected gain is the same kind of number. When the rate flips negative the payment direction flips with it, and the same calculation returns a credit instead of a cost.
From Ratio to Stake: Position Sizing and Kelly
The margin is the stake, and the stake is set from the risk, not from the size of the gain. With a 100,000 account and a 1 percent risk rule, the loss budget per trade is 1,000; the stop two percent below entry on this contract is 1,000 per contract, so the position is one contract and the posted margin is 5,000, which is 5 percent of the account. The Position Sizing tool takes the account, the risk per trade, the entry, and the stop, and returns the number of contracts and the resulting exposure, so the stop distance and the account rule do the arithmetic instead of the trader. Halve the stop distance and the same 1,000 budget buys two contracts, with the same 1,000 at risk and 10,000 posted.
Kelly is the next question: not how large this trade is, but what fraction of the account a strategy like this deserves in general. With a 50 percent win rate and a 2 to 1 reward to risk, the Kelly fraction is 50 percent minus 50 percent divided by 2, which is 25 percent of the bankroll; half Kelly is 12.5 percent, and most working traders live at quarter Kelly or below, because the win rate and the ratio are estimates, not measurements. The Kelly Criterion calculator takes the win rate and the payoff ratio and returns the full, half, and quarter marks, so the sizing rule has a written ceiling instead of a mood.
Read the output in the same order the entry was made: the contract value is the exposure, the margin is the stake, the return on margin is the percent the move prints, the scenario table is the week in advance, the comparison table is the temptation with its price, and the funding line is the cost of holding the answer. Every number was computed in the tab that holds the position, and none of it was sent anywhere. The calculator does not decide the trade; it makes the trade a number you can refuse.