n8n website change detection, self hosted

Who this is for: anyone who wants to know when a page's actual content changes (competitor pricing, terms of service, a product page) without paying for a SaaS change-detection tool.

What the workflow does

Every 15 minutes n8n downloads the page, computes a SHA-256 hash of the response body, and compares it against the hash saved from the previous run. If it differs, it sends a Telegram alert. This is not uptime monitoring — a page can stay online (status 200) while its content quietly changes underneath, which is exactly what this catches.

Procedure

1. Download the website-change-watcher.json file.
2. In n8n: Workflows → Import from File and pick the downloaded file.
3. Open the Scarica la pagina node and set the URL you want to watch.
4. Create a Telegram bot (talk to @BotFather, /newbot, copy the token) and put the token and your chat_id in the Avvisa su Telegram node.
5. Activate the workflow.

How it works under the hood

The Code node uses Node's built-in crypto module to hash the raw response body — any byte-level change (a price, a paragraph, a line in a legal page) changes the hash. The first run only saves the baseline hash and doesn't alert; only differences from then on trigger a message, stored via $getWorkflowStaticData so no external database is needed.