RSS Feed Monitoring
DiffHook can monitor any public RSS 2.0 or Atom 1.0 feed and send a notification to your channel of choice the moment a new item is published.
How it works
DiffHook fetches your feed on a regular schedule. When the list of items changes — a new entry appears at the top — it fires a notification with the item title, source, and a direct link.
- Free plan — checked once per hour
- Paid plans — checked up to every minute
No webhooks to maintain, no code to write. Paste the feed URL, pick a notification channel, and you're done.
Setting up an RSS monitor
- Go to Monitors and click New monitor.
- Paste the feed URL in the URL field (e.g.
https://hnrss.org/newest). - DiffHook auto-detects RSS and Atom feeds — no extra configuration needed.
- Choose your polling interval and notification channel.
- Save and activate.
That's it. DiffHook will send a notification to your configured channel as soon as a new item appears.
Supported feed formats
| Format | Example |
|---|---|
| RSS 2.0 | Most news sites, GitHub releases, Reddit, podcasts |
| Atom 1.0 | YouTube channels, arXiv, many developer blogs |
If you're unsure whether a URL is a valid feed, paste it into DiffHook — it will tell you at creation time.
Popular feeds to monitor
| Source | Feed URL |
|---|---|
| Hacker News | https://hnrss.org/newest |
| GitHub releases (any repo) | https://github.com/{owner}/{repo}/releases.atom |
| YouTube channel | https://www.youtube.com/feeds/videos.xml?channel_id={id} |
| Reddit subreddit | https://www.reddit.com/r/{subreddit}/.rss |
| arXiv search | https://arxiv.org/search/?searchtype=all&query={term}&start=0 (use RSS link on page) |
Notification channels
When a new item is detected, DiffHook can route it to any channel you have configured:
- Slack — a rich message in any channel or DM
- Discord — an embed posted to any server channel
- Email — a clean digest to any address
- Telegram — a bot message to any chat or channel
- Webhook — a JSON
POSTto your own endpoint (n8n, Make, Zapier, custom API)
→ See RSS feed notification options for a full comparison of channels and setup guides.
Tracking only new items
DiffHook compares the list of item GUIDs (or <link> values) between polls. Only genuinely new items trigger a notification — items that are edited or re-ordered do not.
If a feed does not include stable GUIDs, DiffHook falls back to comparing item titles. In practice this works correctly for the vast majority of feeds.
Tips for reliable RSS monitoring
Use the most specific feed URL you can. Many sites expose multiple feeds (all articles, a single author, a single category). The narrower the feed, the less noise you get.
Check the feed's <ttl> or Cache-Control header. Some feeds are only updated hourly regardless of how often you poll. Setting your poll interval to match avoids wasted checks.
Combine with a webhook for custom pipelines. If you need to process new items (store them in a database, cross-post to another platform, run a classifier), connect a webhook output and let your backend handle the rest.
Disable or pause monitors you no longer need. Paused monitors do not count against your plan's check budget. See Plans & Billing for details.
Be aware of shared IP rate limits. DiffHook fetches feeds from a shared pool of IPs used across all customers. If many users are monitoring the same popular feed host, the provider's rate limiter may occasionally block requests — even if your individual poll interval is well within their published limits. If you see intermittent 429 errors in the Logs tab, try increasing your poll interval to reduce pressure, or check whether the feed provider offers a dedicated API with higher quotas.
Troubleshooting
No notifications even though the feed has new items
- Confirm the feed URL is publicly accessible (not behind a login).
- Check the Logs tab for the monitor — DiffHook records every check result there, including HTTP errors.
- Some feeds include only the 10 most recent items. If you set up the monitor after items were already published, those items are treated as pre-existing and do not trigger a notification.
Duplicate notifications
This can happen if the feed publisher changes GUIDs after publication. Use the Logs tab to compare snapshots between two consecutive checks.
Feed URL returns HTML instead of XML
Some pages show a "subscribe" UI in the browser but serve a valid XML feed when requested with an RSS Accept header. DiffHook sends the correct headers, but if you copied the URL from the browser address bar you may have the HTML page URL instead of the feed URL. Right-click the RSS icon on the site and copy the link directly.