How to Scrape Public Telegram Channels Without API Keys or Login

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Public Telegram channels have a web preview endpoint at t.me/s/[username] that returns the latest messages as server-rendered HTML, requiring no API key, bot token, or phone number. The endpoint supports pagination via a 'before' query parameter, allowing retrieval of a channel's full message history by stepping through message IDs. Each message block contains the text, timestamp, view count, photo URLs, and forward source, while channel metadata such as title and subscriber count is available via OpenGraph tags on the base channel page. Developers should note that abbreviated counts like '3.4M' or spaced numbers like '11 862 837' require custom parsing to avoid errors. Private channels and those with disabled previews return no message blocks, and data such as reactions, comment counts, and poll results are not available through this method.

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