I Built a Free Trading Journal That Runs Entirely in Your Browser

#webdev #javascript #trading #opensource

Every trading journal I tried wanted me to create an account, hand over my trade data, and pay $15/month for the privilege.

I just wanted to log my trades, see some charts, and figure out if I was actually improving. So I built TradeLog — a trading journal that runs 100% in your browser. No signup, no server, no data leaving your machine.

The Problem with Existing Trading Journals

Most trading journals fall into two camps:

Spreadsheets — flexible but ugly, no charts, easy to break
SaaS apps — pretty but expensive, want your broker API keys, store your data on their servers

If you're a retail trader, neither option is great. You don't need enterprise features. You need a clean way to log entries, see your P&L over time, and spot patterns in your wins and losses.

What TradeLog Does

Log trades with entry/exit price, quantity, date, and notes
Dashboard with Chart.js — P&L curve, win rate, average gain/loss, all visualized
Filter by date range, ticker, or strategy
Import/export CSV — bring your data in, take it out, no lock-in
Everything stays in localStorage — your trades never leave your browser

The whole thing is a single HTML page with vanilla JavaScript and Chart.js. No build step, no framework, no backend.

Why Privacy-First Matters for Trading

Your trade history is sensitive financial data. It reveals your strategies, your risk tolerance, your account size. Handing that to a random SaaS company feels wrong.

With TradeLog, your data lives in your browser's localStorage. Want a backup? Export to CSV. Want to move to another tool? Export to CSV. Want to delete everything? Clear your browser data. You're in control.

The Tech Stack (or Lack Thereof)

HTML + CSS + vanilla JS — one file, zero dependencies (besides Chart.js CDN)
Chart.js — for the P&L dashboard and equity curve
localStorage — for persistence
GitHub Pages — for hosting (free)

Total cost to run: $0/month. Forever.