Position Sizing

The Position Sizing tab controls how many contracts Tempest uses when it trades a signal — either a fixed number per trade, or a size calculated from your account funds and a risk-per-trade setting.

Warning: Trading futures carries substantial risk of loss. Position sizing is a configuration control, not a guarantee of any outcome. You alone are responsible for the size and risk of your trades. See Assisted Trading for how orders are actually placed.

Where to find it

Position Sizing is a tab in the center of the window, grouped with the Assisted Trading and Charts tabs. From here you can:

• See your Available Funds, refreshed about every 2 seconds while connected to your broker
• Switch between Fixed and Dynamic sizing
• Set your contract count (Fixed) or risk level (Dynamic)
• See a preview of the size Tempest expects to use on the next trade

📷 Screenshot: The Position Sizing tab showing Available Funds, the Fixed/Dynamic mode radios, the Contracts-per-trade control, and the "Next trade" preview line at the bottom.

Available Funds

At the top of the panel, Available Funds: shows the buying power reported by your broker connection, formatted as a dollar amount (for example, $50,000.00).

• It shows -- (not connected) when Tempest is not connected to your broker or has not yet received an account figure. See Connecting to Interactive Brokers to restore the connection.

Available funds is the figure Tempest uses for Dynamic sizing. It reflects buying power available for new positions and changes as you open and close trades.

Sizing Mode: Fixed vs. Dynamic

The Sizing Mode: row has two radio buttons: Fixed and Dynamic. Fixed is selected by default.

Fixed sizing

In Fixed mode, Tempest uses the same contract count on every trade, regardless of account size or stop width.

• Control: Contracts per trade: — a number box, range 1 to 100.
• Default: 1 contract per trade.
• Example: Set it to 2, and Tempest aims to trade 2 contracts on each signal.

Fixed mode is a good starting point while you confirm that assisted trading behaves as you expect.

Dynamic sizing

In Dynamic mode, Tempest calculates the contract count from three inputs:

• Your Available Funds
• A risk-per-trade percentage (chosen with the Low / Med / High radios)
• The stop distance of the signal — how far the stop sits from the entry price

In plain language, Tempest works out how many dollars the chosen percentage of your account represents, then divides that by how much one contract would lose if the trade hit its stop, and rounds down to whole contracts:

Risk dollars   = Available Funds × Risk percentage
Per-contract   = Stop distance × the contract's dollar-per-point value
Contracts      = floor( Risk dollars ÷ Per-contract )

The result is then clamped: it is never smaller than your Contracts per trade value, and never larger than an internal cap (default 10). The cap is also never lower than your Contracts-per-trade value.

Note: Because the floor of the calculation is your Contracts-per-trade value, Dynamic mode will never place fewer contracts than Fixed mode would. If the math works out below that number, Tempest uses the Contracts-per-trade value instead.

Risk levels (Dynamic mode only)

The Risk per trade: row offers three radio buttons. Low is selected by default.

A higher percentage risks more of your account on each trade, which generally produces a larger contract count. Choose the level you are comfortable with; none of these guarantees a particular result.

How the stop distance affects size

Tempest measures the stop distance from the signal's entry price to the stop level the signal carries — using the signal's wider scale-in stop level when one is present. The wider the stop, the more each contract could lose at the stop, so Dynamic mode computes fewer contracts. A tighter stop produces more.

If the stop distance is essentially zero or invalid (less than one tick), Tempest cannot size against it and falls back to Fixed sizing for that trade, using your Contracts-per-trade value.

When Available Funds is zero or unavailable

If the account figure is zero or not yet available, Dynamic sizing has nothing to size against, so Tempest falls back to Fixed sizing and uses the Contracts-per-trade value.

Worked example

• Available Funds: $50,000
• Risk level: Low (0.5%) → risk dollars = $50,000 × 0.5% = $250
• Stop distance: 10 points on a contract worth $50 per point → per-contract risk = 10 × $50 = $500
• $250 ÷ $500 = 0.5, rounded down = 0 → below the floor, so Tempest uses your Contracts per trade value instead.

Raise the risk level, increase funds, or trade a signal with a tighter stop to compute more than the minimum.

The "Next trade" preview

At the bottom of the panel, a blue line shows the size Tempest expects to use on the next trade.

• Default text: Next trade: — contracts (shown before a figure is available).
• Fixed mode: for example, Next trade: 2 contracts.
• Dynamic mode: for example, Next trade: ~3 contracts (0.5% risk, 10-pt stop). The tilde (~) marks it as an estimate.

Note: In Dynamic mode the preview is an estimate only. It assumes a typical 10-point stop to illustrate sizing. The actual contract count is computed per signal from that signal's real stop distance, so it may differ from the preview.

The preview refreshes about every 2 seconds along with Available Funds.

Scale-in trades

Some signals include scale-in levels — additional entry legs at further price levels. With those signals, Tempest does not add a separate full-size position for each leg. Instead, it splits the trade's total size across the legs:

• A signal with one scale-in level splits the total roughly in half (initial entry + scale-in 1).
• A signal with two scale-in levels splits it across three legs (initial entry + scale-in 1 + scale-in 2).

So that every scale-in level the signal carries actually gets placed, Tempest enforces a minimum total of one contract per leg. For example, a signal with one scale-in level will place at least 2 contracts total (1 initial + 1 scale-in), and one with two scale-in levels will place at least 3, even if your sizing setting was lower.

For the full mechanics of how these legs, stops, and targets work together, see Brackets & Scale-In.

Saving and defaults

Your sizing choices are saved on your computer and restored the next time you open Tempest. They are local to this machine and do not sync across devices.

Suggestions

• Start with Fixed sizing while you confirm assisted trading and signal behavior, then move to Dynamic if you prefer risk-based sizing.
• Watch Available Funds. In Dynamic mode, as funds fall the computed contract count tends to fall with them; as funds rise it tends to rise — always within your Contracts-per-trade floor and the cap.
• Mind your stops. Very wide stops shrink the Dynamic count toward your minimum, since each contract risks more at the stop.
• Test before going live. Use the Test Orders control in the Assisted Trading tab to confirm sizing behaves as you expect before enabling live trading.

Warning: Trading futures carries substantial risk of loss. Signals and any AI commentary are informational only — not recommendations, advice, or guarantees of accuracy or results. You are solely responsible for your sizing configuration and your trades. Past performance does not guarantee future results. Never trade with money you cannot afford to lose.

Related pages

• Assisted Trading — Enabling and confirming order placement — you approve each trade
• Brackets & Scale-In — How multi-leg entries, stops, and targets work
• Connecting to Interactive Brokers — Setting up the broker connection
• Positions & Orders — Monitoring open positions and working orders