PolyChart - Candlestick Charts

Professional K-line charts for Polymarket prediction markets

PolyChart - Candlestick Charts Stop squinting at flat probability lines. Start reading the market like a trader. Polymarket shows you a single price line and a percentage. That works if all you want to know is "what's the current number." But if you're trying to time entries, spot reversals, or understand how a market actually moves throughout the day — a flat line tells you nothing. You can't see support and resistance. You can't see momentum shifts. You can't tell if a price dropped because of real volume or just a thin order book blip. And you definitely can't overlay multiple outcomes to see which side of a market is gaining strength. That information exists in the data. You just don't have the right chart. WHY POLYMARKET CHARTING IS SO HARD Prediction markets move differently from stocks or crypto, but the principles of technical analysis still apply. The problem is access: - Polymarket only shows a basic line chart with no timeframe controls - There are no candlestick charts, so you can't read open/high/low/close patterns - There's no way to add indicators like RSI or moving averages - Multi-outcome markets show each outcome separately, never overlaid for comparison - There's no price alert system, so you have to manually check prices Most traders end up refreshing the page repeatedly or copying prices into spreadsheets. That's slow, error-prone, and you'll miss moves while you're not watching. PolyChart solves this by injecting a professional candlestick chart directly onto every Polymarket event page. WHAT THIS EXTENSION DOES PolyChart is a Chrome extension that adds a floating, resizable candlestick chart widget to Polymarket event pages. It automatically detects the market you're viewing, fetches historical price data from the Polymarket CLOB API, and renders interactive K-line charts using the TradingView Lightweight Charts library. No spreadsheets. No external charting tools. No copy-pasting data. The chart appears right on the page where you're already making decisions. Here's what you get: Candlestick Charts — Full OHLC (Open, High, Low, Close) candles with green/red coloring. See the actual price action structure, not just a smoothed line. Multiple Timeframes — Switch between 1-hour, 4-hour, and 1-day candles to analyze different time horizons. Pro users also get 5-minute and 15-minute candles for intraday analysis. OHLC Data Display — Hover over any candle to see the exact open, high, low, and close values in the info bar below the chart. Interactive Crosshair — Full crosshair with time and price axes. Zoom in and out, pan across the timeline, and pinpoint exact price levels. Draggable and Resizable Window — Position the chart anywhere on the page. Drag from the header bar, resize from any edge or corner — just like a desktop application window. Minimize to a small floating button when you need more screen space. Dark Theme — Designed to match Polymarket's dark interface. The chart blends into the page without visual clutter. PRO FEATURES Upgrading to Pro unlocks tools that serious traders need: 5-Minute and 15-Minute Timeframes — See intraday price action at high resolution. Useful for timing entries around news events or market shifts. Technical Indicators — Overlay Moving Average (MA-20), Exponential Moving Average (EMA-12), and Bollinger Bands directly on the main chart. RSI (14-period) and MACD appear in a dedicated sub-panel below the chart. Multi-Outcome Overlay — Compare up to 8 outcomes on a single chart with color-coded lines. See how "Yes" and "No" prices move relative to each other, or compare all candidates in a multi-outcome market at once. A legend bar shows which color maps to which outcome. Volume Histogram — Proxy volume bars at the bottom of the chart show relative activity for each candle period. Green bars for up-candles, red for down-candles. Price Alerts — Set a target price and direction (above or below). When the market hits your level, you get a desktop notification. Never miss a breakout or breakdown again. CSV Data Export — Download the current chart data as a CSV file with Date, Open, High, Low, Close, and Volume columns. Use it in spreadsheets, backtesting tools, or your own analysis scripts. HOW IT WORKS 1. Install the extension from the Chrome Web Store 2. Navigate to any event page on polymarket.com (URLs containing /event/) 3. The chart widget appears automatically in the bottom-right corner 4. Click timeframe buttons (1H, 4H, 1D) to switch candle periods 5. Drag the header bar to reposition, drag edges to resize 6. Hover over candles to see OHLC values That's it. The chart loads within seconds and updates when you switch timeframes. No account required for free features. WHY A FLOATING WIDGET Browser popups disappear the moment you click away. Side panels take up permanent screen space. A floating widget stays visible while you scroll the page, read comments, and check order books — but you can drag it out of the way or minimize it to a tiny button when you need full screen space. Resize it larger when you want a detailed view. It behaves like a tool window in a desktop trading application. PRICE ALERTS Set alerts directly from the chart. Choose a price level and direction — "above 65 cents" or "below 40 cents" — and receive a desktop notification when the market reaches that level. Alerts are checked every 60 seconds by the background service worker. All alert data is stored locally in your browser. Nothing is sent to external servers. CSV EXPORT Click the CSV button to download the current chart data. The file includes every candle's timestamp, open, high, low, close, and volume count. File names include the outcome name, timeframe, and date for easy organization. Useful for importing into Google Sheets, Excel, Python scripts, or backtesting frameworks. REAL SCENARIOS WHERE THIS HELPS Timing an entry on a political market: A presidential election outcome is trading at 42 cents. The 1H chart shows three consecutive green candles bouncing off a support level at 38 cents. RSI is climbing from oversold territory. You decide to enter now rather than waiting for 35 cents. Spotting a fakeout on a news event: Breaking news sends a market from 60 to 75 cents in minutes. The 5M chart shows a long upper wick and immediate reversal — a classic rejection candle. You hold off on buying the spike and wait for a pullback to 65. Comparing outcomes in a multi-candidate race: Five candidates in a primary. The overlay chart shows Candidate A's line crossing above Candidate B's for the first time. The trend has been building for three days on the 4H chart. This crossover pattern helps you decide which position to take. Setting a dip-buy alert: A market you're watching is at 55 cents but you want to buy at 45. Set a "below 45" alert and go about your day. Your phone buzzes when the price hits your target. Exporting data for a model: You're building a simple mean-reversion model for prediction markets. Export 1H candle data for 10 markets as CSV files, load them into a Jupyter notebook, and backtest your strategy on real Polymarket data. Evaluating volatility before a deadline: A market resolves in 48 hours. The 15M Bollinger Bands show the price compressing into a tight range — low volatility before a potential breakout. You size your position accordingly. WHAT THIS EXTENSION DOES NOT DO - It does not access your Polymarket account or wallet - It does not place trades or interact with any smart contracts - It does not send your browsing data to external analytics services - It does not modify Polymarket's page content beyond injecting the chart widget The permissions it uses: - storage — Save your preferences, Pro token, and alert settings locally - alarms — Check price alerts every 60 seconds in the background - notifications — Send desktop notifications when a price alert triggers - tabs — Detect when you navigate to a new Polymarket page - host_permissions (clob.polymarket.com) — Fetch historical price data from the public CLOB API - host_permissions (polychart.dsonline.workers.dev) — Verify Pro subscription tokens All preference and alert data stays in your browser's local storage. Chart data is fetched from Polymarket's own public API — the same data the Polymarket website itself uses. FREE VS PRO The free tier includes everything you need for basic charting: - Candlestick charts with 1H, 4H, and 1D timeframes - OHLC data display with crosshair - Draggable, resizable, minimizable chart window - Dark theme matching Polymarket Pro ($12.99/month, $129/year, or $89 one-time lifetime) adds: - 5M and 15M short timeframes - Technical indicators (MA, EMA, RSI, MACD, Bollinger Bands) - Multi-outcome overlay comparison - Volume histogram - Price alerts with desktop notifications - CSV data export Free users see Pro features with a lock icon. No nag screens, no popups asking you to upgrade. The free version is a fully functional charting tool. THE INDICATORS Moving Average (MA-20) — Simple 20-period moving average. Shows the average closing price over the last 20 candles. Plotted as an amber line on the main chart. Exponential Moving Average (EMA-12) — 12-period EMA that responds faster to recent price changes. Plotted as a pink line. Useful for spotting short-term trend direction. Bollinger Bands (20, 2) — Upper, middle, and lower bands based on 20-period MA and 2 standard deviations. Shows when price is extended (touching upper/lower band) or compressed (bands narrowing). RSI (14) — Relative Strength Index in a separate sub-panel. Values above 70 suggest overbought conditions, below 30 suggest oversold. Useful for spotting potential reversals. MACD (12, 26, 9) — Moving Average Convergence Divergence in a sub-panel. Shows the MACD line (blue), signal line (amber), and histogram. Crossovers between the MACD and signal lines indicate potential trend changes. WHO THIS IS FOR - Polymarket traders who want to see candlestick patterns instead of flat lines - Technical analysts who use indicators like RSI and MACD for timing decisions - Multi-outcome market watchers who need to compare outcomes on a single chart - Data-driven traders who export market data for backtesting or modeling - Anyone who checks Polymarket daily and wants a better visual experience GETTING STARTED Install the extension from the Chrome Web Store, open any Polymarket event page, and the chart appears automatically. No account needed. No sign-up. No configuration. Just candlesticks, right where you need them.