RSS & Atom Date Format Converter

Q: What is the RSS pubDate format?

RFC 822 style: **`Thu, 13 Aug 2026 14:30:00 +0000`**. RSS 2.0 requires this exact form (RFC 822 per spec, RFC 2822 accepted in practice).

Q: What is the Atom date format?

W3C DTF (RFC 3339/ISO 8601): **`2026-08-13T14:30:00Z`**. Atom requires a timezone; `Z` is most common.

Q: What is the iCalendar date-time format?

Basic ISO 8601 without separators: **`20260813T143000Z`** for UTC, or `20260813T143000` for floating (local) times with a `TZID` property.

Q: Can I use one format for both RSS and Atom?

Stick to each spec: **RFC 822 for RSS, RFC 3339 for Atom**. Validators reject mismatches, and mixing dialects is a top cause of feed validation failures.

Web feeds timestamp in three different dialects: RSS `pubDate` uses RFC 822 style (`Thu, 13 Aug 2026 14:30:00 +0000`), Atom `updated` uses W3C DTF / RFC 3339 (`2026-08-13T14:30:00Z`), and iCalendar uses `DTSTART` values (`20260813T143000Z`).

This converter renders your date-time in all four feed forms so you can generate spec-compliant feeds or debug why a feed validator rejected a timestamp.

Timezone:

Enter a date-time above to see the conversion results.

RSS & Atom Date Format Converter Quick Reference

Format	Pattern / Description	Example 1	Example 2
RSS (RFC 822)	Feed Date	Thu, 13 Aug 2026 14:30:00 +0000	Thu, 01 Jan 2026 00:00:00 +0000
Atom (RFC 4287)	ISO 8601 (Z)	2026-08-13T14:30:00.000Z	2026-01-01T00:00:00.000Z
iCalendar (ICS)	DTSTART/DTEND	20260813T143000Z	20260101T000000Z
W3C DTF	YYYY-MM-DDThh:mm:ssTZD	2026-08-13T14:30:00.000Z	2026-01-01T00:00:00.000Z

* Examples are rendered in UTC for the fixed sample instants above.

When to Use RSS & Atom Date Format

Feed generation

Generate RSS 2.0 `pubDate` and Atom `updated` values that pass W3C feed validators without guessing the dialect.

Feed validation debugging

When a validator rejects your feed, compare your timestamp against the required dialect for that element.

Calendar event integration

Build iCalendar (.ics) files with correct `DTSTART`/`DTEND` values in the compact basic format.

Frequently Asked Questions

What is the RSS pubDate format?

RFC 822 style: `Thu, 13 Aug 2026 14:30:00 +0000`. RSS 2.0 requires this exact form (RFC 822 per spec, RFC 2822 accepted in practice).

What is the Atom date format?

W3C DTF (RFC 3339/ISO 8601): `2026-08-13T14:30:00Z`. Atom requires a timezone; `Z` is most common.

What is the iCalendar date-time format?

Basic ISO 8601 without separators: `20260813T143000Z` for UTC, or `20260813T143000` for floating (local) times with a `TZID` property.

Can I use one format for both RSS and Atom?

Stick to each spec: RFC 822 for RSS, RFC 3339 for Atom. Validators reject mismatches, and mixing dialects is a top cause of feed validation failures.

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