About sizeforzero
A trading journal that keeps the numbers honest and reads your own notes back to you.
sizeforzero is a minimalist trading journal for stocks and single-leg options, built in Canada. Your broker fills arrive on their own or by CSV, the numbers stay honest, and Iris, the AI inside, reads the notes you wrote and tells you in plain words what you keep doing. It never places an order.
What is sizeforzero?
A trading journal for stocks and single-leg options. It is a journal, not a broker: it records what you did and why, and it never places an order, holds funds or gives investment advice.
Fills reach the journal two ways. Brokers connect read-only and refresh daily, or you drop in a CSV. From there the journal keeps an equity curve, a calendar of closed P&L by day and a handful of core statistics, with the position page for the detail: your fills on the price chart, your thesis and your notes.
The journal is free forever, with unlimited trades and every account. The brokers page lists what connects, and the pricing page has the plans. It is built in Canada and serves traders in Canada and the US.
What does the name mean?
Size for zero: size every position so the worst case costs you nothing you can’t afford to lose. The name is the first rule, and the journal is the rest.
The rest of the rule is to trade the plan you wrote and to read yourself back honestly. The position size calculator turns the first part into a share count.
How does Iris write from my own notes?
Iris reads the notes you wrote, with your trades and results beside them, and answers in plain prose. It repeats your own words back as a pattern; it does not predict a trade or tell you what to do.
On Free, Iris writes two reflections a month, one monthly letter, a monthly digest and the lessons rulebook. On Pro it is always on: a daily reflection, the Sunday letter, a read on every position and the patterns it notices ranked by what they cost you. Every letter is kept indefinitely, so you can read what you were doing to yourself last September. The post on writing notes an AI can read back explains what makes a note worth reading.
What data goes to the AI?
Nothing, until you turn AI processing on. It is a separate decision from signing up, and you can switch it off any time in Settings.
When it is on, a request carries:
- Your trades: ticker, the dates you opened and closed, days held, quantity and average cost.
- Your results: profit and loss on closed trades, win rate and period totals. Never balances or portfolio value.
- Your labels: setup, mood and conviction, from short fixed lists.
- Your notes, as you wrote them, with email addresses and phone numbers removed.
- Habits counted from your closed trades, how your results compare with public market indexes, and any question you type to Iris.
It never carries your name, email address, handle, IP address, device identifier, broker, account numbers, balances or payment details. The one identifier an overnight request carries is a random request code with an internal account number inside it, so the result reaches the right person. The AI is provided by Anthropic, whose commercial terms forbid training on this data and which keeps request logs for up to 30 days. Your notes are never sold. The AI section of the privacy policy has the full list, the retention period and how to withdraw consent.
Does sizeforzero give advice or place trades?
No. It never places an order, moves money or gives investment advice. Iris is a mirror, not an oracle: its reflections are informational and past performance does not guarantee future results.
How do I contact sizeforzero?
Write to support@sizeforzero.com. It is the one address for questions and problems.
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