Check your feed with Feeder's free RSS feed validator. It lists each error with its line and how to fix it, and shows what Feeder reads from your feed. Feeder reads feeds that aren't perfect, but a valid feed works in every reader and avoids the problems below.
The W3C Feed Validation Service is a good second check.
Use the right date format
RSS dates look like Sat, 26 Sep 2026 09:00:00 GMT, with a four-digit year. Use your language's built-in function for it:
- PHP:
date(DATE_RSS) - Python:
email.utils.format_datetime(dt) - Ruby:
Time.now.rfc2822, afterrequire "time" - JavaScript:
new Date().toUTCString() - Go:
t.Format(time.RFC1123Z)
Avoid PHP's DATE_RFC822 and Go's time.RFC822. They write a two-digit year, which validators reject or warn about.
Give every post a GUID
The <guid> element is a unique ID for each post. Feeder uses it to tell new posts from ones it has already seen. Without a GUID, Feeder goes by the title and the date, so if you edit a title or a date, the post shows up again as new.
Any value works as long as it is unique and never changes, for example the post's permanent address.
Keep IDs and dates stable when you move
If you change your site's time zone, domain or publishing platform, keep each post's GUID and date the same. If they all change at once, readers may see every old post as new.
Let Feeder reach your feed
If Feeder says it can't reach your feed, check that your firewall or Cloudflare doesn't block our crawlers. See What to do if Feeder's crawlers are blocked by Cloudflare and Feeder servers' public IP addresses.