This list is inspired by awesome public datasets, but for real-time datasets and sources. Normally accessed via HTTP or Websockets.

The list is separated into Free and Paid and broken into subsections based on loose categories.

• Coinbase Market Data - Coinbase websocket to market data including level 2 orderbook data.
• Blockchain transactions - Provides real-time notifications about new transactions and blocks.
• Yahoo Financewss://streamer.finance.yahoo.com/ - This is not advertised in developer documentation, but discoverable as the websocket is used to update their website.
• Finnhub - Limited free usage with a premium data sources also available.
• CoinCheck - a cryptocurrency API that has a WebSocket interface (in beta)
• Alpaca Markets Real-Time and historical market data via HTTP and Websocket.

• Open Rail Data - A collection of APIs that provide data relating to the UK rail network, including reference data, train timetables, and live service updates. The live data is streamed using the STOMP protocol.
• GBFS New York - GBFS is the standard for bike share data with many locations around the world. Find more information here
• Open Sky Flight - Data from Open Sky Api via HTTP endpoint. Supports real-time, but not streaming. Need to continually poll.
• MTA GTFS Feed - Transit data in GTFS format for transit systems like NYC subway and Caltrain.

• Wikimedia SSE Event Stream of recent changes to the wikimedia foundation pages.
• Seismic Data Seismic Portal provides a websocket interface to real-time seismic events.
• Open Weather API - Current weather data available free at rate of 1 request per second.
• Clima Cell - Real-time weather data in a free or paid API.
• NOAA Buoy Data - Real-time buoy data from NOAA
• NOAA Weather Data - Live Weather Data API from NOAA
• Redfin Realestate - pull uptodate data from redfin unofficial API.
• EPA Airnow data - Air quality data hosted by the EPA.
• UK Flood Data - UK government real-time API for flood data.

• GitHub Events - Use the GitHub API to consume public events happening on GitHub.
• EventSim - Tool to simulate event data

• IEX Trading - IEX was created in response to questionable trading practices that had become widely used across traditional exhcanges! Their API provides streaming Stock market data.
• Twitter - Twitter provides a streaming interface for research or enterprise. It is unknown what support will be post Twitter purchase in 2022.

• AIS Data Maritime, Aviation and weather data available via Spire.

• PurpleAir Air Quality Data - Developer API for accessing purple air sensor data.