Copy ratio is the one setting that decides whether a copied trade fits a follower account or overwhelms it. Get it right and every account trades at a size that makes sense for its own rules. Get it wrong, and a copier just multiplies the same mistake across every connected account at once.
What a copy ratio actually is
A copy ratio scales the leader's trade size for one specific follower. 1.0x mirrors the leader exactly - the same contract count, the same trade. 0.5x copies at half that size. 2.0x doubles it. The ratio is set per follower, not globally, so two followers connected to the same leader can end up trading completely different sizes off the exact same signal.
Why 1.0x is a default, not a rule
It's tempting to leave every follower at 1.0x, since it's the setting nobody has to think about. But a follower rarely matches the leader exactly - different starting capital, a tighter daily loss limit, or a smaller evaluation account running next to a larger funded one. Set the ratio to fit what that specific follower can actually absorb, not whatever's easiest to leave alone.
Size the ratio against the follower's own limit, not the leader's account
Start from the follower's own daily loss limit, not the leader's account size. If a follower's limit is roughly half the leader's, a ratio near 0.5x keeps the trade proportionally about as risky on both accounts. The number only holds up if you actually check both accounts' real limits before setting it - a ratio picked without that comparison is a guess wearing a decimal point.
The mistake that ages badly: setting it once and forgetting it
A ratio that's correct on day one can be wrong six weeks later without anyone touching the setting - a firm resets a limit after a scaling milestone, or you move to a bigger evaluation account, and the old ratio no longer fits. Revisit every follower's ratio whenever that account's own rules change, not just at initial setup.
Set the ratio with the follower's Copy toggle off, then flip it on and watch the first couple of trades land in the Event Log - the resulting size at that ratio will be right there, so you can confirm it actually makes sense for that account before you let it run unattended.
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