A backtesting journal is only useful if you wrote down the reason for each entry before you knew how the trade ended. It isn't about which fields you record. It's about the exact moment in the replay when you record them. That difference rarely gets mentioned, and it's what separates a useful journal from one that only confirms what you already wanted to see.
You already have the field template
If you're still not sure what to record for each trade (candle date, entry, stop and target prices, reason and execution note), our step-by-step backtesting guide includes that full template. This article assumes you already know it and goes one step further: the real problem usually isn't which fields are missing, but when they get filled in.
The problem no template solves
Imagine you jump the replay ahead ten candles at once. You see that price broke a support level and rallied hard, and only then do you go back to the breakout candle to "log" your entry. The "reason for entry" you write at that point isn't a real decision. It's a justification built on information you didn't have at the real moment of that candle. Our complete guide already identifies this as hindsight bias, the sneakiest of the common backtesting mistakes. This article focuses on how to avoid it specifically when you keep your journal.
The 'reason for entry' field is only worth something if you wrote it before you knew the result, never after.
See plansContaminated journal vs. clean journal
| What you record | Clean journal | Contaminated journal |
|---|---|---|
| Reason for entry | On the exact decision candle, before moving forward | After seeing several more candles, with the result already known |
| Tone of the notes | Includes doubts: "wasn't sure about the context" | Every note sounds equally sure and convincing |
| Result | Recorded when the trade closes (it's fine for this to come later) | Recorded at the same time as the reason, not separately |
| Real usefulness | Shows how you actually trade, so you can genuinely fix it | Shows how you'd like to think you traded |
The three-moment logging routine
Split the record for each trade into three separate moments, and never get ahead of any of them:
- Before you enter. Write down the reason for the entry as soon as your rule is met, on that same candle, before you move the replay forward even one more candle.
- When you execute. Record your entry price, stop and target at that same instant, with no pause between deciding and logging.
- When you close. Only now, with the trade already settled, record the result and an honest execution note ("followed it exactly" or "hesitated halfway through").
A simple rule to keep the order intact: if you ever feel tempted to "fill in" a field you left blank several candles back, that trade is already contaminated. Keep it as a lesson about your process, but leave it out of your final statistics.
Candle-by-candle replay keeps you from seeing the chart's future. Logging at the right moment is still up to you.
See plansSigns your journal is already contaminated
- All your entry notes sound equally confident, with no doubts recorded anywhere.
- You don't remember writing the reason before you saw where price went.
- Your backtesting win rate is much higher than the one from your first demo account trades using the same strategy.
- You look through your own journal and can't find a single trade where "the read was right but it lost." Every loss gets blamed on something outside your control.
If you recognize two or more of these signs, it's worth restarting your practice session with the three-moment routine instead of piling more trades onto an already distorted base. Once your journal is clean, the next step is learning how to read your backtesting statistics.
Frequently asked questions
- Which fields should I record in my backtesting journal?
- The date and time of the entry candle, your entry, stop and target prices, the reason for the entry in one sentence, and an execution note. Our step-by-step guide covers all of that in detail. This article focuses on something else: when to record each field, not which fields to record.
- Is it wrong to record a trade's result after it closes?
- No. The result (win, loss or breakeven) only exists once the trade plays out, so recording it at that point is correct. What contaminates your journal is writing the reason for the entry after you've seen the result, not the result itself.
- How can I tell if hindsight bias has already crept into my journal?
- If every entry note you read sounds equally convincing, with no doubts and no misreads anywhere, that's a sign they were written with the result already known, not at the real moment of the decision.
- Does a journal in Excel or Notion work for this too?
- It works for recording the fields, but it doesn't solve the underlying problem. Nothing in a spreadsheet stops you from skipping ahead a few candles, seeing the result, and filling in the row as if you'd written it earlier. The real safeguard is your habit, not the recording tool on its own.
- How many trades do I need in my journal before drawing conclusions?
- At least 30-50 complete trades, the same minimum we recommend in the step-by-step guide, but only if those trades were recorded at the right moment. Fifty trades in a contaminated journal are worth less than thirty in a clean one.
- Does Trade & Repeat force you to record at the right moment?
- The replay moves forward one candle at a time and doesn't let you see the chart's future, so your entry decision is locked to the real moment. Writing it down honestly at that instant, without getting ahead of yourself mentally, is still up to you.
Keep reading: How to backtest a forex strategy step by step · Trading backtesting: the complete guide to getting started · Confirmation bias in backtesting: why you only review your winning trades · Cherry-picking without realizing it: why your backtesting date range isn't neutral
Educational content only; it is not financial advice. Trading financial markets involves the risk of losing capital.