How it works
The simulator loads a history of daily ECB reference rates and hides everything after a chosen starting date. You see the past, decide whether to buy, sell or wait, then advance one day at a time to reveal the next rate. Your virtual balance updates as positions gain or lose value.
Because the replay uses one reference rate per working day, it is best suited to practicing slower, multi-day decision-making: reading a trend, planning a stop and target, and sticking to a position size.
What the data does and doesn't include
- Included: one daily ECB reference rate per currency against the euro, from which cross rates can be derived.
- Not included: intraday highs and lows, live bid and ask prices, weekend data or tick-by-tick movement.
The rates are reference rates for information, not executable trading quotes. See the Currency Converter for more on how they are set.
Formula
Open P/L uses the same logic as our Profit/Loss Calculator:
- Buy: (current rate − entry rate) × units
- Sell: (entry rate − current rate) × units
The result is in the quote currency and is converted to your virtual account currency. Virtual equity = virtual balance + open P/L.
Worked example
These figures are illustrative.
You start with a virtual balance of $10,000. On day 1, the replayed EUR/USD reference rate is 1.0850, and you buy 10,000 units.
| Day | EUR/USD rate | Open P/L | Virtual equity |
|---|---|---|---|
| 1 | 1.0850 | $0 | $10,000 |
| 2 | 1.0870 | +$20 | $10,020 |
| 3 | 1.0835 | −$15 | $9,985 |
| 4 | 1.0890 | +$40 | $10,040 |
On day 4, P/L = (1.0890 − 1.0850) × 10,000 = 0.0040 × 10,000 = $40.
Suppose your stop-loss was 1.0830. On day 3 the reference rate was 1.0835, so the simulator would keep the trade open. In a live market, the price could have dipped below 1.0830 during that day and triggered your stop. This is the key limitation of daily data, and a good reminder that real outcomes can be worse than a replay suggests.
Tips
- Write a plan before each trade. Decide entry, stop-loss, target and size first, then advance the days.
- Use realistic sizes. Size positions with the Lot Size Calculator as you would with a real account; oversized virtual trades teach bad habits.
- Record your trades in the Trading Journal to review them later.
- Try different periods. Trending and range-bound stretches test different skills. See Technical analysis basics.
- Don't overfit. Doing well on one historical stretch says little about future markets.
Risk note
The simulator is a practice tool only. Results are hypothetical and based on historical reference rates, which differ from the prices you would actually trade at. Success in a simulation does not mean you will succeed with real money. Live trading carries a substantial risk of loss.
Frequently asked questions
What data does the simulator use?
It replays historical daily euro foreign exchange reference rates published by the European Central Bank. There is one rate per working day, with no intraday highs or lows.
Is the virtual balance real money?
No. The balance is virtual and has no cash value. Nothing you do in the simulator places a real trade.
Why can't I see intraday price moves?
The source data contains a single reference rate per day. Prices between those daily points are unknown, so the simulator can only move from one day to the next.
How is a stop-loss handled with daily data?
The simulator can only compare stops and targets with each day's reference rate. In real markets, a price might touch your stop during the day and recover before the close, which this data can't show.
Will results in the simulator match live trading?
No. Real trading involves bid and ask prices, spreads, commissions, swap, slippage and emotional pressure that a daily replay can't fully reproduce.