The Position Size Calculator is an indicator that sits directly on your TradingView chart. You set your trade details — where you plan to enter, where you'd place your stop loss, and your profit target — and it instantly shows you exactly how large your position should be, how much of your account is at risk, and whether the trade is worth taking.
Think of it like a risk calculator that lives on your chart. No more jumping between spreadsheets or doing maths in your head while the market is moving.
⚡ Key Takeaways
- The R:R ratio is controlled entirely by your Entry, Stop Loss, and Target prices — not by Risk % or Leverage.
- Risk Percentage controls how many dollars you lose if stopped out. Set this first, set it honestly.
- Leverage controls how much of your own cash (margin) is committed. It does not change your dollar risk.
- ROE measures return on margin, not your full account — don't use it to justify sizing a position up.
- Never adjust Risk % or Leverage to make a bad trade look better — fix the setup or skip the trade.
- Beginners: start at 1x leverage until you fully understand how margin and risk interact.
What is this tool?
Most beginners lose money not because they pick bad trades, but because they risk too much on a single trade. This tool puts position sizing front and centre so it becomes a habit — not an afterthought.
Once it's on your chart, you fill in six values in the settings panel and the indicator draws a visual profit zone (green) and loss zone (red) to the right of price — along with a stats table showing every number you need before entering the trade.
✅ Why this matters: Consistent position sizing is one of the only things separating traders who survive long-term from traders who blow up. Even a 50% win rate is profitable if you consistently risk less than you gain. This tool makes that consistent sizing automatic.
The six inputs — what each one does
Open the indicator settings by clicking the cog icon next to the indicator name on your chart. You'll see six fields under the Inputs tab. Here's exactly what each one controls:
Your total trading account size in dollars. This is the number everything else is calculated from. Update it whenever your balance changes significantly.
Example: $1,000What percentage of your account you're willing to lose if this trade hits your stop loss. This is the most important input — it directly sets your maximum dollar loss on the trade.
Example: 1.2% = $12 at riskHow much the exchange multiplies your position beyond your own capital. Higher leverage means less of your own money is tied up, but losses and gains grow at the same rate.
Example: 10x leverageThe price you plan to enter the trade. This is where you expect to buy (for a long) or sell (for a short).
Example: $2,212 (ETH)The price where you exit if the trade goes against you. The gap between Entry and Stop Loss drives your position size — a wider stop means a smaller position for the same dollar risk.
Example: $2,180 (32 pts below)Your profit goal — the price you expect the trade to reach. Used to calculate potential profit and your Reward-to-Risk ratio. Move this until you achieve 2:1 or better.
Example: $2,280 (68 pts above)⚠️ Stop Loss Placement: Your stop should sit at a level that genuinely invalidates your trade idea — typically just below a recent swing low (a price trough where the market previously bounced back up). That's the point where, if broken, your trade idea is simply wrong. Placing a stop purely to keep the Risk $ number small — without reference to price structure — is one of the most common beginner mistakes. Read the Market Structure guide to understand swing highs and lows in detail.
What the calculator shows you
After entering your settings, these results appear in the stats table on your chart and in the visual zones to the right of price. Here's what each number means:
⚠️ ROE is not your account return: A 30.74% ROE sounds impressive — but that's the return on the margin committed ($82.95), not your full $1,000 account. The actual account gain is $25.50 ÷ $1,000 = 2.55%. Higher leverage inflates the ROE number without changing your dollar profit at all. Never use a high ROE as a reason to increase your position size.
Step-by-step: how to use it
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1
Add the indicator to your chart. Open TradingView, click "Indicators" and search for the Trade Logic Position Size Calculator. Add it. It doesn't plot candle data — it overlays information to the right of price once you configure it.
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2
Open the settings panel. Click the cog icon next to the indicator name. You'll see the Inputs tab with the six fields. Start by entering your Account Balance and Risk Percentage — these two control every dollar amount the calculator produces.
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3
Set your trade levels. Enter your Entry price, Stop Loss, and Target. Look at the chart and choose levels that make structural sense. Your stop should sit just below a meaningful swing low — a previous price trough where buyers stepped in and pushed price back up. Not a round number you picked to keep the risk figure small.
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4
Check the R:R ratio first — before anything else. If it's below 1.5, the trade probably isn't worth taking. The sweet spot is 2:1 or higher. If R:R is too low, adjust your Target to a more ambitious structural level or skip the trade. Never widen your stop or increase Risk % to compensate for a poor R:R.
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5
Set your leverage. Adjust leverage to control how much of your capital is committed as margin. Beginners should start at 1x (no leverage) — this eliminates liquidation risk and makes the relationship between risk and reward easy to understand. The calculator works perfectly at 1x. Increase leverage later once position sizing feels natural.
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6
Confirm and enter the trade. The green and red zones on your chart are a visual sanity check — does the trade look reasonable against recent price action? If yes, use the exact Position Size the calculator gives you. Don't round it up "to make it a cleaner number." That's how you accidentally risk more than you intended.
Same trade, different settings — worked examples
The same ETH trade (Entry: $2,212 | Stop Loss: $2,180 | Target: $2,280) shown with two different configurations. The R:R stays at 2.13 in both — because R:R is only ever determined by your price levels, never by Risk % or Leverage settings.
💡 What the examples show: R:R is identical (2.13) in both. What changes is capital efficiency. Example B uses far less margin ($82.95 vs $276.50), freeing $193.55 for other trades. Example A risks more in absolute dollars but commits more capital too. Neither is automatically better — it depends on how many positions you want to run simultaneously.
Risk % vs Leverage — what's the actual difference?
This is the question that confuses most beginners. Both settings affect how big your trade is — but they control completely different things. Changing one when you should change the other is one of the most common sizing errors.
Controls how much you can afford to lose. Setting 1% means if your stop loss is hit, you lose exactly 1% of your account. This is your pain threshold — set it honestly before you open any trade.
Controls how much of your actual cash (margin) is required to hold the position. 10x means you only need 1/10th of the position value as a deposit. It does not change your dollar risk.
This is the result of your Risk % and Leverage settings combined. Don't manually adjust it. If you're touching position size directly by eye, you've already lost control of your risk.
When to change each setting
| Setting | When to increase | When to decrease | What it does NOT change |
|---|---|---|---|
| Risk % | ✓ High conviction trade with clear structure ✓ Strong HTF trend confirmation ✓ After a genuine positive streak (and only slightly) |
✗ After consecutive losses ✗ Uncertain or choppy market conditions ✗ Wide stop losses on high-volatility assets |
Your R:R ratio. R:R is purely price-based. |
| Leverage | ✓ Running multiple positions simultaneously ✓ Tight stop and margin is high relative to your account ✓ Experienced traders freeing capital intentionally |
✗ When you're new — default to 1x or 2x ✗ In highly volatile market conditions ✗ When your stop loss is already very wide |
Your dollar risk (that's set by Risk %). Your R:R ratio. |
✅ Beginners: use 1x leverage first. At 1x, your position size equals your margin, there's no liquidation risk beyond your stop loss, and the maths is straightforward. The calculator works perfectly at 1x. Once position sizing feels like second nature, start experimenting with 2x–5x to understand how margin efficiency changes — but your dollar risk should stay exactly the same.
Pros and cons of the tool
| Feature | Pros | Watch outs |
|---|---|---|
| On-chart display | ✓ Visual green/red zones keep you grounded in actual price action ✓ No mental arithmetic while watching live markets |
✗ You must update Entry/Stop manually as price moves — stale inputs mean stale outputs |
| Risk % control | ✓ Enforces consistent risk across every trade ✓ Protects against emotional over-sizing in the heat of the moment |
✗ Only works if you're honest about setting it conservatively and keeping it there |
| Leverage input | ✓ Makes margin usage visible and deliberate ✓ Helps you run multiple positions efficiently |
✗ High leverage + wide stop = potential liquidation before your stop is even hit. Always check margin vs account balance ratio |
| ROE display | ✓ Useful for comparing capital efficiency between setups ✓ Shows leveraged return on committed margin |
✗ Looks far more impressive than the actual account % gain. Never use ROE as the primary reason to enter a trade |
| R:R ratio | ✓ Instant go/no-go signal for trade quality ✓ Stops you taking setups where risk exceeds potential reward |
✗ R:R alone doesn't account for win rate. A 3:1 trade you lose 80% of the time is still unprofitable overall |
Common mistakes — and how to avoid them
If the R:R is below 1.5, the right answer is to find a better trade or adjust your Target to a more realistic level — not to risk more to inflate the potential profit figure. Changing Risk % does not improve R:R at all. It just means you lose more when the trade fails.
Increasing leverage doesn't increase what you earn in absolute dollar terms — your dollar gain is determined by Risk % and R:R. The only things higher leverage changes are how little margin you commit, and how quickly you get liquidated if price moves sharply against you before hitting your stop. Use it for capital efficiency, not as a profit amplifier.
Moving your stop closer to entry just so the calculator shows a lower risk figure is backwards. Your stop should sit at a level that genuinely invalidates your trade idea — typically just below a swing low (a previous price trough where buyers pushed price back up). A stop that's too tight gets taken out by normal price noise before the trade has a chance to work.
If one trade uses $82.95 margin on a $1,000 account, that's fine. But five open trades each using $200 margin commits your entire account. The calculator shows per-trade margin — tracking the total across all open positions is your responsibility. Always maintain a mental or written running total.
If price moves and you decide to enter at a different level, update Entry, Stop Loss, and Target in the settings before using the output. The calculator is only as accurate as the numbers you give it. Stale inputs produce stale — and dangerous — position sizes.
The rules — save these
Before every trade, run through this checklist. If you can't tick all five, don't enter.
📋 Pre-Trade Checklist
- R:R is 2:1 or higher — if not, pass on the trade or move the Target to a more ambitious structural level
- Risk % is set at 1–2% maximum — never exceed this until you have months of consistent, documented results
- Stop Loss is at a structurally valid level — just below a swing low, not a round number that "feels close enough"
- Total margin across all open trades is manageable — you should never have your entire account committed
- You can emotionally accept losing the Risk $ amount shown — if you can't stomach that loss, reduce the Risk %
⚠️ The golden rule: Never change your Risk % or Leverage to make a bad trade look like a good one. The tool shows you the truth about a trade. If the numbers don't work, the trade doesn't work — no amount of settings adjustment changes that reality.
Frequently Asked Questions
Risk Per Trade percentage is the portion of your account you're willing to lose if your stop loss is hit. At 1% on a $1,000 account, the maximum you can lose on that trade is $10. It directly controls your dollar risk regardless of what leverage you're using.
No. Increasing leverage does not increase your dollar profit — that's set by your Risk % and R:R ratio. Leverage only controls how much of your own capital (margin) is required to hold the position. Higher leverage means less margin tied up, but it also amplifies liquidation risk if price moves sharply against you before your stop is hit.
Most professional traders look for a minimum R:R of 2:1 — meaning the potential profit is at least twice the potential loss. Below 1.5:1 the trade is usually not worth taking. R:R is determined entirely by your Entry, Stop Loss, and Target prices — not by any other setting in the calculator.
ROE stands for Return on Equity — it shows your profit as a percentage of the margin you committed, not your total account. Because leverage reduces the margin, ROE rises with leverage even though your actual dollar profit is unchanged. Always check your estimated dollar profit relative to your full account balance for an honest picture of what the trade is worth.
Beginners are better off starting at 1x (no leverage) or very low leverage such as 2x–3x. At 1x, your margin equals your position size, there is no liquidation risk beyond your normal stop loss, and the relationship between risk and reward is completely transparent. The calculator works perfectly at 1x. Increase leverage later, once you're comfortable with how margin and position sizing interact.
Put Your Structure Knowledge to Work
Understanding market structure tells you which direction to trade and where to place your stop. The Position Size Calculator ensures you enter with the right size every time — so that even when structure shifts unexpectedly, your risk stays controlled.
Open the Calculator →