How to keep a trading journal that improves your decisions
What to write in a trading journal, a simple daily, weekly and monthly review routine, and how to measure rule-following separately from profit and loss.
Part of the Psychology and Discipline track on Agenticks. About 10 minutes, written for a intermediate reader.
Read first: Overconfidence and overtrading.
Last reviewed .
Key takeaways
- A journal turns memory, which is biased by outcomes, into a record you can review.
- Record the setup, the reason, the size, the planned exit, the result and how you felt, before the result is known where possible.
- Measure rule-following separately from profit and loss, because a good result can come from a broken rule and a loss from a good trade.
- A short daily entry, a weekly review of the rule-following rate and a monthly look at results by setup is a routine most people can keep.
Memory is a poor record of trading. It keeps the dramatic wins and losses, forgets the dull trades in between, and quietly edits what you were thinking once the outcome is known. That last effect, hindsight bias, is strong enough that people rarely notice it happening. A trading journal is the fix: a written record of each decision, made at the time, that the result cannot rewrite. There is evidence that the act of recording matters. A meta-analysis of 138 experiments with almost 20,000 participants found that prompting people to monitor their progress toward a goal helped them reach it, and the effect was larger when progress was physically recorded or reported. Most of those studies were about health habits rather than markets, but the mechanism, seeing your own behavior in writing, carries over. This works for investors too. An investment journal records why you bought, what would prove that reason wrong, and when you will next look, so a later decision can be checked against the original thinking rather than the price.
What to record Keep it short enough that you will actually do it. Six fields cover most of what matters: 1. Setup. Which of your defined patterns or conditions this was. If it fits none of them, write that. 2. Reason. One sentence on why you are taking it, written before entry. 3. Size. Shares or contracts, and the money at risk if the stop is hit. 4. Plan. Entry, stop and target, decided in advance. 5. Result. Profit or loss in money and in R, the loss you planned to take. A trade that risked $200 and made $300 is +1.5R. 6. Emotion. One or two words: calm, rushed, bored, angry, sure. Patterns in this column are often the most revealing. Then add one more line that changes everything: did I follow my rules, yes or no?
Score the process, not just the outcome
A good trade can lose and a bad trade can win. If you only score profit and loss, you will reward lucky rule-breaking and punish disciplined losses. Track rule-following as its own number.
Worked example: one month, two scores
A trader logs 20 trades in a month and marks each one as following the rules or not. Illustrative numbers.
| Trades that followed the rules (average +$100 each) | 14, net +$1,400 |
|---|---|
| Trades that broke the rules (average -$150 each) | 6, net -$900 |
| Total profit and loss (1,400 - 900) | +$500 |
| Rule-following rate (14 / 20) | 70% |
| What the totals hide | The broken-rule trades cost $900 |
The month looks fine on profit alone. Split by rule-following, the cheapest improvement is obvious: stop taking the trades the plan does not allow.
- Followed the plan
- Took a valid setup and hit the planned stop for -1R, Exited at the planned target for +2R, Stopped trading for the day after reaching the daily loss limit
- Broke the plan
- Moved the stop lower and the trade recovered for +0.5R, Doubled size on a hunch and won +3R, Skipped a valid setup after two losses, and it would have won
A review routine you can keep After each trade or at the end of each day (5 minutes): fill in the fields and the yes or no on rules. Do not analyze yet. Weekly (20 minutes): work out the rule-following rate, and the profit and loss of followed and broken trades separately. Pick the single most common mistake and write one change for next week. Monthly (an hour): look at results by setup. Which setups have a positive average result, measured as in our lesson on expectancy? Be careful with small numbers: ten trades of one setup says very little, as the lesson on sample size shows. Investors can run the same routine on a slower clock: a note for every buy and sell, and a review each quarter that compares each holding with the reason written when it was bought.
Put the steps for a single trade's journal entry in order, from first to last.
- Name the setup and write the reason
- Record the size and the money at risk
- Write the planned entry, stop and target
- Record the result in money and in R
- Mark whether the rules were followed and note the emotion
What a journal tends to reveal After a month or two of honest entries, patterns appear that memory would never have surfaced. Some common ones: The emotion column predicts the result. Trades marked rushed, bored or angry often lose more than trades marked calm. That is a reason to add an if-then rule for those states, not a reason to trust feelings as signals. The first loss of the day changes behavior. Many traders find that their worst trades come straight after a loss, when the urge to win it back is strongest. One setup carries the results. Often one or two setups produce most of the profit and the rest roughly break even or lose after costs. Dropping the weak ones can matter more than finding new ones. Winners get cut short. Comparing planned targets with actual exits often shows profits taken early, the disposition effect from the lesson on loss aversion. Size creeps up after a good week. Recording the money at risk on every trade makes that drift visible. Mistakes that make a journal useless Writing entries days later, from memory, brings hindsight straight back in. Logging only the losing trades, or only the interesting ones, skews every number. A form with twenty fields gets abandoned within two weeks. And a journal nobody reviews is a diary, not a tool. The review routine above exists to stop that last one.
A journal shows you where the plan breaks. The final lesson in this track, on sticking to a plan, covers the tools that keep it from breaking in the first place.
You can keep a useful journal
You know what to record for each trade, how to score rule-following separately from profit, and a review routine that turns entries into decisions.
Check your understanding
- Why should the reason for a trade be written down before the result is known?
- Because once the outcome is known, hindsight rewrites what you remember thinking. Hindsight bias makes the outcome look obvious and blurs your original reasoning. A note made in advance cannot be rewritten.
- Over 20 trades, the 14 that followed the rules made +$1,400 and the 6 that broke them lost $900. What is the rule-following rate?
- 70%. 14 of 20 trades followed the rules: 14 / 20 = 0.70.
- A trader moved a stop lower and the trade came back for a small profit. How should the journal classify it?
- Broke the plan, even though it made money. The result was good but the process was not. Rewarding it teaches a habit that will eventually turn a small loss into a large one.
- Why is a monthly review of results by setup more reliable than a daily one?
- A day holds too few trades to say much; a month gives a larger sample. A handful of trades is mostly noise. Results per setup only start to mean something with more trades.
Common questions
- What should I write in a trading journal?
- At minimum: the setup, the reason for the trade, the size, the planned entry, stop and target, the result, and how you felt. Adding whether you followed your rules lets you measure discipline separately from profit.
- How often should I review my trading journal?
- A common routine is a short entry after each trade or each day, a weekly review of how often you followed your rules, and a monthly review of results by setup, when there are enough trades to say something.
Terms defined in this lesson
Continue
- Previous: Overconfidence and overtrading
- Next: How to stick to a trading or investment plan
- Sample size and why ten trades mean nothing
- Reading results 2: expectancy and profit factor
- Loss aversion and the disposition effect
- What is programmatic / statistical trading
- Psychology and Discipline track
- All Agenticks lessons
- Trading glossary
Sources
- Fischhoff, B. (1975). Hindsight is not equal to foresight: The effect of outcome knowledge on judgment under uncertainty. Journal of Experimental Psychology: Human Perception and Performance, 1(3), 288-299.
- Harkin, B., Webb, T. L., Chang, B. P. I., Prestwich, A., Conner, M., Kellar, I., Benn, Y., & Sheeran, P. (2016). Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychological Bulletin, 142(2), 198-229.
Written and reviewed by the Agenticks Learn editorial team. How we write and check lessons.
Agenticks Learn is general education. It is not financial, investment, tax or legal advice, it does not take your situation into account, and nothing on it is a recommendation to buy, sell or hold any security or to open any account. Examples use illustrative numbers. Investing involves risk, including losing money you put in, and past performance does not predict future results. Tax rules and limits change; the official sources linked in each lesson are the final word.