London Strategic Edge streams live market data over a single WebSocket connection covering more than 4,000 instruments: roughly 3,900 US and international stocks, 60 forex pairs, 58 cryptocurrencies, 23 commodities, 25 ETFs, 13 indices, and live options chains for 500 US stocks. One API key subscribes to any symbol with no per symbol fees and no separate exchange entitlements to manage. Ticks arrive as compact JSON the moment the market prints them, so charts, trading bots and dashboards update in real time instead of polling a REST endpoint on a timer. The browser playground on this page lets you paste a key, connect, subscribe to symbols and watch the raw feed before you write a line of code. The free tier includes 50 GB of monthly payload, and the same key also pulls history over plain HTTP from the download API. Comparable real time data feeds charge hundreds of dollars per month per asset class. This one is free.
