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Trading Infrastructure

Lot Multiplier vs Fixed Lot: Copier Risk by Account Size

One lot is 1% risk on a $100k master, 10% on a $10k follower. Trada's three sizing modes, Lotsize Multiplier, Fixed Lotsize and Fixed % Risk, translate that gap differently.

Updated 8 min read

Why Lot Sizing Mode Matters

A trade copier does not copy lot sizes. It translates them. A 1-lot trade on a $100,000 master account is 1% risk. The same 1-lot trade copied to a $10,000 follower account is 10% risk. Without a sizing step in between, the copy scales risk by the ratio of the account sizes.

The lot sizing mode is how the copier does that translation. Pick the wrong one and risk drifts apart across accounts. Pick the right one and each follower takes the exposure you intended. Trada has three modes. Each receiver (the follower account) picks its own in its Trading tab, independently of the sender (the master account) and of the other receivers. The rest of this article covers what each mode does and when it holds.

Quick Answer

Trada has three lot-sizing modes, set per receiver: Lotsize Multiplier (the default), Fixed Lotsize and Fixed % Risk. For accounts of different sizes, use Lotsize Multiplier with the Suggest button, which sets the multiplier to receiver balance divided by sender balance. The multiplier then stays fixed until you change it.

3Sizing ModesLotsize Multiplier · Fixed Lotsize · Fixed % Risk
1Default ModeLotsize Multiplier
perReceiver ConfigurationEach receiver configured independently

The Three Lot Sizing Modes

Lotsize Multiplier

The default mode, and what most traders mean by a lot multiplier. The copier takes the sender's lot size and multiplies it by a value you set.

Example: Sender trades 1.0 lots. Multiplier is 0.5. Receiver opens 0.5 lots.

When it works: The receiver's balance is a known proportion of the sender's. A $50,000 receiver copying a $100,000 sender at a 0.5 multiplier carries the same proportional risk.

When it fails: The multiplier is static. It does not follow later changes in either balance, so after a payout, a withdrawal or a drawdown the proportion drifts until you set the value again.

Fixed Lotsize

The receiver opens the same lot size on every trade, whatever the sender trades and whatever the balances are.

Example: Fixed at 0.20 lots. Whether the sender opens 0.50, 1.00 or 2.00 lots, the receiver opens 0.20 lots every time.

When it works: An account that has to trade one set size, or a test of a copier configuration at a small size before going live.

When it fails: Any setup where the sender varies size on purpose. The receiver ignores that variation, so its risk per trade no longer tracks the sender's.

Fixed % Risk

The receiver risks a fixed percentage of its account on every trade. Trada calculates the lot size from that percentage and the stop-loss distance.

Example: 1% risk on a $10,000 receiver puts $100 at risk. With a 50-pip stop-loss, the lot is sized so that the stop costs about $100.

When it works: Strategies where every trade carries a stop-loss. Each trade is sized to lose the same percentage if stopped out, whatever the stop distance.

When it fails: It needs a stop-loss to size against: the sender's, or one configured in the receiver's SL & TP settings. Without one the trade is not copied, or, if Force Minimum Lot Size is on, it is copied at the broker's minimum lot size.

Proportional Sizing With the Suggest Button

Trada has no mode that recalculates the ratio from balance or equity on every trade. A balance % or equity % mode is not among the three. Proportional sizing is done with Lotsize Multiplier and its Suggest button.

Formula: Suggested multiplier = Receiver balance / Sender balance

Example: Sender balance $50,000, receiver balance $5,000. Suggest sets the multiplier to 0.10. If the sender opens 1.00 lot, the receiver opens 0.10 lots.

Suggest uses the balances at the moment you click it. The multiplier then stays fixed: it does not follow later changes in either balance. The proportion is as current as your last click, so click Suggest again when the balances drift apart. The help page on lot-sizing modes shows where the button sits.

Max Lot Size and Force Minimum Lot Size

Two advanced settings on the receiver's Trading tab bound the result of whichever mode you pick.

  • Max Lot Size caps the final size after the mode is applied. A computed 3.50 lots with a 2.00 cap is sent as 2.00.
  • Force Minimum Lot Size raises a calculated size to the broker's minimum when it would otherwise be too small. It matters most with Fixed % Risk on a small receiver.

Which Mode for Which Setup

Setup TypeModeWhy
Receivers of different sizesLotsize Multiplier, set with SuggestSets the multiplier to the balance ratio; repeat when balances change
Receivers the same size as the senderLotsize Multiplier at 1.0Simplest configuration when account sizes match
An account that must trade one set sizeFixed LotsizeSame lot on every trade, whatever the sender does
A strategy with a stop-loss on every tradeFixed % RiskSizes each trade from the stop distance; needs a stop-loss

Lot Sizing and Prop Firm Rules

Prop firm accounts add one constraint that changes the calculus: the daily loss limit. The lot sizing mode sets how far a single adverse trade can move a receiver account relative to that limit.

Sizing Mode
Risk Predictable per Trade
Scales with Account Balance
Fixed Lotsize
Lotsize Multiplier
As of the last time it was set
Fixed % Risk

For prop firm setups, two things have to hold: risk is predictable per trade, and it scales with account balance. Fixed Lotsize holds neither. Lotsize Multiplier holds the first, and holds the second only as of the last time the multiplier was set. Fixed % Risk holds both, on the condition that every trade has a stop-loss.

Set your lot sizing mode before setting daily loss protection thresholds. If the sizing is wrong, the risk per trade differs from what the thresholds were planned around.

For more on protection thresholds, see the trade copier risk management guide. For the full setup process across prop firm accounts, see how to copy trades across prop firm accounts.

Common Mistakes

MistakeWhy It FailsFix
Using Fixed Lotsize across accounts of different sizesRisk % is inconsistent: a 0.1 lot is a different share of a $100k account than of a $10k accountUse Lotsize Multiplier and set the value with Suggest
Setting a multiplier once and never revisiting itThe value is static, so after a payout, a withdrawal or a drawdown it no longer matches the balancesClick Suggest again when balances change
Using Fixed % Risk without a stop-lossThere is no distance to size against, so the trade is not copied, or is copied at the broker minimum if Force Minimum Lot Size is onPut a stop-loss on every sender trade, or configure one in the receiver's SL & TP settings
Leaving a 1.0 multiplier on mismatched account sizesA 1.0 multiplier on a $10k receiver copying a $100k sender carries ten times the intended riskSet the multiplier to receiver balance / sender balance

Getting the Configuration Right

The lot sizing mode is configured per receiver. Before going live:

  1. 1Note the sender balance and every receiver balance.
  2. 2Choose the mode for each receiver: Lotsize Multiplier for proportional copying, Fixed Lotsize for a set size, Fixed % Risk when every trade has a stop-loss.
  3. 3With Lotsize Multiplier, click Suggest to set the value to receiver balance / sender balance.
  4. 4Set Max Lot Size if the account has a position-size limit.
  5. 5Place a minimum-lot test trade on the sender. Check that each receiver opens the lot size you expect.
  6. 6Only after that check: configure protection thresholds against the lot sizes you confirmed.

A misconfigured mode carries the wrong risk on one or more accounts on every trade from that point on. The test trade costs a spread. Set the mode per receiver, confirm it on a minimum-lot test trade, then configure protection thresholds against the lot sizes you confirmed.

Frequently Asked Questions

Sources

  1. 1.Trada documentation: Lot-sizing modes, docs.trada.io/copy-trading/configure-receiver/lot-sizing-modes (checked 8 October 2026)

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