For the
Long-term investor
Days-held next to every position, a concentration flag when one name dominates, and a Sunday letter that reflects on conviction — not session discipline. Export to CSV anytime.
A journal for the trades you’ll still believe in next year.
Track conviction, not noise. Every position carries the thesis you wrote at entry; the AI reads your notes back to you in your own voice — quietly, only when you open the app. Built for investors who hold for months and review by the year.
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app.sizeforzero.com/dashboard
DASHBOARD · TODAY
AAPL is 38% of your book.
Holds
6
Avg hold
72d
This month
+$2,847
Win rate
—
PLTR is your strongest book — 76.5% win rate.
Trust signals
Built solo by Dhruv in Scarborough, ON. No VC, no investors, no data sale ever.
PIPEDA + CCPAPasswordless authFree forever tier
The position ritual
Three small acts that compound into conviction.
We don’t ask you to journal every minute. We ask you to journal every position. Ten minutes when it matters — when you open, when conviction wavers, when you close.
01— WHEN YOU OPENSoon
Write the thesis
One paragraph: why now, where you'd cut, what counts as a no-go. Lives on every position so it's there months later when you're tempted to forget. The standalone Thesis view ships with the Journal feature.
02— WHILE YOU HOLD
Revisit conviction
A concentration band on Trades flags when one name has taken over your book. Days-held and cost basis sit next to every open position so you remember why you took it. Press L from anywhere to log a new trade.
03— WHEN YOU CLOSE
Read the verdict
Calendar marks the closes; Reflect shows your win rate and profit factor next to the trades that made them. Premium adds a Sunday letter written from your week.
What’s inside
Built for investors who write things down.
Not 100 features you’ll never use. The handful that earn their keep when you re-read them next year.
AI · QUIET, NOT LOUD
Patterns surface themselves.
A short reflection on the trades you closed — written in plain English when you open the app, never pushed at you. Premium adds a Sunday letter, written by Claude from your own trades.
SOMETHING I NOTICED
Your PLTR trades sized into the trend averaged +$143 each across the last 17 attempts. The shape is the same every time.
Premium · written for you every Sunday.
CALENDAR HEATMAP
A month, at a glance.
Green when you closed in the green. Red when you didn’t. Click any day to drill into every trade you closed that day.
THE NUMBERS THAT MATTER
Three figures, not a hundred.
Win rate, profit factor, and closed-trade volume — the exact triad already on the Reflect page. No composite score, no false-equivalence grade; just the inputs your eyes can read.
TRADE JOURNALING
Every trade, with intent.
Thesis, conviction grade, and a note on every execution — captured at the moment you take or close the trade, not in a separate ritual you forget to do. Your reflections live where they happened.
THESIS · WHY THIS TRADE
SPY reclaimed 528 with volume. NVDA pulled to the rising 20MA — taking starter long, adding only on hold above 186.
Who it’s for
One journal. Two kinds of investor.
Same calm, same restraint, same plain-English glossary. Pick the row that’s closest to how you hold.
For the
Swing trader
Calendar heatmap to spot drift, per-symbol P&L to find your edge, and a calm space to write your thesis.
From the founder
I built this for the trades I’d still believe in next year. Quiet enough that it earns my evening, honest enough that I re-read what I wrote.
— Dhruv, Scarborough · ON
Imports — the honest version
CSV in. Works with every broker.
We don’t pretend to have native broker integrations yet. Drag your broker’s CSV onto the Data Hub and we’ll parse it. Native integrations land once enough users tell us which broker to start with.
Interactive BrokersRobinhoodTD / SchwabFidelityWebulltastytradeTradierAny broker via CSV
Why traders switch to sizeforzero
Less is more. Here’s how we compare to spreadsheets and the feature-bloated alternatives.
Feature
Sheet
Other journals
SfZ
Free tier forever (no time limit)
Calendar P&L heatmap with day drill-in
Trade journaling (thesis + tags)
Plain-English glossary for beginners
Passwordless auth (magic link)
AI-written weekly letter (Premium)
Unified Stocks + Options trade list
No data selling, ever
Built for daily use, not yearly tax
100+ overwhelming metrics
Soon = on the public roadmap. We label it explicitly instead of leaving it ambiguous.
FAQ