Ready to go further
Next: see what costs do to an edge
The slippage guide shows how a small cost per trade changes the result of a strategy with a small edge per trade.
What is included
- What it is, in plain words
- The formula or mechanism, with exact arithmetic
- How it hits grid, martingale and DCA bots
- A check you can run before you switch a bot on
Who it is for
- People who run or plan to run a trading bot
- Anyone reading a backtest or a bot sales page
- Readers who want the numbers, not the pitch
- Not advice, and not a signal service
Key facts
- Copy trading means your account opens and closes positions automatically when a chosen leader's account does. You hold no rule of your own. You hold the leader's.
- A leader record shows what happened, not why. Luck, a short history, a large account and hidden risk all look like skill on a chart. See survivorship bias.
- A follower never gets exactly the leader's fills. Delay, spread and slippage are extra cost on every trade, and the costs add up with the number of trades.
- Worked example (made-up): the same 240 trades made 24.0% for the leader and 15.4% for the follower, because of 1.8 extra pips of cost per trade (calculated by us on 29 Oct 2026, exact).
- Copying moves the risk, it does not remove it. A follower can lose more than the leader did if sizing, timing or the stop rules differ.
How copying works
A leader trades their own account. A copy system watches that account and sends each new order, change and close to every follower account. Each follower has a setting that decides the size. The two common settings are a fixed size, for example always 0.10 lot, and a proportional size, where the follower's size is the leader's size times the ratio of the two balances.
The copy is a second order, placed a short time after the first. It is not a shared fill. The follower's order goes to the market on its own and gets its own price. How long the delay is, which orders are copied and what happens on a failure depend on the service, so read the rules of the one you are looking at and test them on a demo account.
What a leader's record can hide
One lucky run
If many people trade at random, some of them will have a great year. Take a made-up pool of 200 leaders who have no skill at all, each with a fair coin for every month. The chance that one of them is up in 10 or more of 12 months is 1.93%, and across 200 leaders about 3.9 of them are expected to show it. A list sorted by past return is a list of the lucky as much as the skilled.
Leaders who disappeared
Leaders who blew up or stopped usually leave the list. What remains is the survivors. A list with no failures in it overstates how good the typical leader was.
A short history
Twelve months can be one market mood. A record that never saw a sharp reversal, a long sideways stretch or a crash has not been tested on them. See overfitting and forward testing.
The size of the leader's capital
A percent return on a large account and on a small one are not the same thing. A large account may use tiny risk per trade and a small one may use huge risk to show the same percent. Look at the drawdown beside the return (see maximum drawdown), and at the largest open loss at any time, not only at closed trades. A position held through a deep loss can be absent from a closed-trade record.
Worked example: why the follower earns less
Everything here is made up. A leader has a $50,000 account and trades 1.00 lot, worth $10 a pip. A follower has $2,000 and copies proportionally, so the ratio is 0.04 and the follower trades 0.04 lot, worth $0.40 a pip. Both take the same 240 trades. The leader averages 5.0 pips per trade. The follower gets the same trade 0.7 pip worse on entry and 0.7 pip worse on exit, and pays 0.4 pip more in spread or commission.
| Item | Leader | Follower |
|---|---|---|
| Account | $50,000 | $2,000 |
| Lot size per trade | 1.00 | 0.04 |
| Pips per trade after costs | 5.0 | 3.2 |
| Pips over 240 trades | 1200 | 768 |
| Result in dollars | $12,000 | $307.20 |
| Result as percent of account | 24.0% | 15.4% |
Calculated by us on 29 Oct 2026, exact. The follower kept 64.0% of the leader's pips, so 36.0% went to the gap between the two fills. Nothing went wrong in this example: every trade was copied. That is the normal case. If the leader's edge per trade had been 1.8 pips or less, the follower would have lost money on trades the leader made money on. Fast, frequent strategies suffer most. See slippage and spread.
How it hits bots
- Grid and martingale leaders can show a smooth rising line for months, because the loss is held open and the wins are closed. The drawdown shows up in one event, and a follower with a smaller account reaches a margin call sooner. See martingale and margin call.
- Automated leaders change settings between versions. The record you read may be several different bots joined together.
- Copying a bot adds a second layer of delay and cost on top of the bot's own.
How to check before any money
- Ask how long the record is, and whether it includes the leaders who stopped.
- Read the largest drawdown and the longest time below a previous high, not the best month.
- Find out how the copy handles size rounding, a missed order and a leader who changes a stop.
- Run the copy on a demo account first and compare your fills with the leader's trade by trade. See paper trading.
- Set a loss limit on the follower side that does not depend on the leader.
What this page does not tell you
It does not say copying cannot work, and it names no service. It says a chart of past returns is weak evidence and a follower pays costs the leader does not. The numbers are made up and nothing here is a recommendation.
Keep Going
Related Tools and Guides
Keep exploring
FAQ
Frequently Asked Questions
What is copy trading?
It is a setup where your account automatically opens and closes the same trades as a chosen leader. The size is set by a rule such as a fixed lot or a ratio of balances.
Why does a follower earn less than the leader?
The follower's orders are placed a moment later and get their own prices, so each trade carries extra slippage and cost. The effect grows with the number of trades and shrinks with a larger edge per trade.
Does a good past record mean the leader has skill?
Not by itself. With many leaders, some will have a strong year by luck alone, and leaders who failed are often missing from the list. Look at record length, drawdown and the method.
Can a follower lose more than the leader?
Yes. A smaller account, different lot rounding, a missed close or a worse fill in a fast market can all make the follower's loss larger in percent terms.
How can I test copying without risking money?
Run it on a demo account and compare each fill with the leader's. Demo fills are often cleaner than live ones, so treat the result as a best case.
Are the numbers on this page real?
Example numbers are made up to show how the maths works, and the page says so. A figure only counts as exact when the page says it was calculated on a stated date. Nothing you enter in a calculator leaves your browser.
Can I use this to decide whether to run a bot?
It can show whether a bot's numbers hold together and how much an account can lose. It cannot say what the market will do, and it is not advice. Use it to ask better questions, then read the terms of your own broker or exchange.
Is this financial advice?
No. It is general education. All example numbers are made up and nothing here is a recommendation to copy anyone.
Know the Risk Before You Run It
Free calculators and guides, added every week. Leave your details and we will email you when new ones go up.
Trading carries a risk of loss