• NIP-74: Podcasts
  • Event kinds
  • Podcast Show (kind:30074)
    • Required tags
    • Recommended tags
    • Content
  • Podcast Episode (kind:30075)
    • Required tags
    • Recommended tags
    • Audio media
  • Podcasting 2.0 alignment (optional)
    • Nostr-native tag formats (recommended)
    • Podcasting 2.0 compatibility tag formats (optional)
    • Mapping guidance (Podcast Namespace → NIP-74 tags)
    • Other RSS/iTunes fields (not Podcast Namespace)
  • Notes
  • Discovery
  • Client behavior
  • Examples
    • Podcast Show
    • Podcast Episode

§NIP-74: Podcasts

NIP-74 example site: https://www.transmit.fm/

Podcasts

draft optional

This NIP defines addressable events for podcast shows and episodes, optimized for metadata, discovery, and long-lived references.

This NIP is compatible with Podcasting 2.0 metadata. Clients and publishers may mirror Podcasting 2.0 fields as tags while keeping Nostr-native semantics.

§Event kinds

• 30074: Podcast Show
• 30075: Podcast Episode

§Podcast Show (kind:30074)

Represents a podcast show.

§Required tags

• d - unique show identifier (recommended: podcast:guid:<guid> or a stable slug)
• title - show title

§Recommended tags

• summary - short description
• language - BCP-47 language code (e.g. en, en-US)
• explicit - content rating (true/false or clean/explicit)
• image - show artwork URL
• r - website or RSS feed URL (repeatable)
• i - external IDs via NIP-73 (e.g. podcast:guid:<guid>, podcast:publisher:guid:<guid>)
• t - categories/keywords (repeatable)
• p - Nostr pubkeys for hosts/producers (repeatable)
• person - people with roles (repeatable, format below)
• funding - funding URL (repeatable, optional label)
• value - value container (see Podcasting 2.0 alignment below)
• value_recipient - value recipients (repeatable, see format below)
• content-warning - if applicable (NIP-36)

§Content

content MAY include a longer description.

§Podcast Episode (kind:30075)

Represents a single podcast episode, linked to a show.

§Required tags

• d - unique episode identifier (recommended: podcast:item:guid:<guid> or a stable slug)
• title - episode title
• published_at - unix timestamp (string) of original publication
• a - reference to the show: 30074:<pubkey>:<d>

§Recommended tags

• i - external IDs via NIP-73 (e.g. podcast:item:guid:<guid>, optional show podcast:guid:<guid>)
• duration - episode length in seconds (string)
• season - season number (string)
• episode - episode number (string)
• episode_type - full, trailer, or bonus
• language - BCP-47 language code (e.g. en, en-US)
• explicit - content rating (true/false or clean/explicit)
• image - episode artwork URL (if different from show)
• t - categories/keywords (repeatable)
• p - Nostr pubkeys for guests/hosts (repeatable)
• person - people with roles (repeatable, format below)
• chapters - chapters URL and MIME type (e.g. application/json+chapters)
• transcript - transcript URL and MIME type (repeatable, optional language/rel)
• soundbite - highlight time range in seconds (repeatable; duration recommended 15–120s)
• funding - funding URL (repeatable, optional label)
• value - value container (see Podcasting 2.0 alignment below)
• value_recipient - value recipients (repeatable, see format below)
• content-warning - if applicable (NIP-36)

§Audio media

Episodes SHOULD include one or more imeta tags (NIP-92) describing audio variants, using fields from NIP-94. At minimum:

• url - audio file URL
• m - MIME type (e.g. audio/mpeg, audio/mp4)
• x - SHA-256 of the file (hex)

Optional fields include size, duration, bitrate, image, and fallback.

§Podcasting 2.0 alignment (optional)

The following tags mirror common Podcasting 2.0 fields. They are OPTIONAL and intended to improve interoperability with RSS-based tooling and indexers.

§Nostr-native tag formats (recommended)

These tags have Nostr-first semantics. Use them even if you are not mirroring RSS.

• explicit - true/false or clean/explicit
• language - BCP-47 language code (e.g. en, en-US)
• duration - episode length in seconds (string)
• episode - episode number (string; decimal allowed)
• season - season number (string; integer recommended)
• episode_type - full, trailer, or bonus
• image - single artwork URL (lossy vs <podcast:image>)
• p - Nostr pubkey references for people associated with the show/episode

§Podcasting 2.0 compatibility tag formats (optional)

These tags mirror Podcast Namespace RSS tags and should preserve required/optional fields where possible.

• person - ["person", "<name>", "<role?>", "<group?>", "<href?>", "<img?>"]
• Example: ["person", "Ada Lovelace", "host", "cast", "https://example.com", "https://example.com/ada.jpg"]
• Example: ["person", "Ada Lovelace", "host", "cast", "nostr:nprofile1...", "https://example.com/ada.jpg"]
• Defaults: role=host, group=cast. Episode-level person tags replace all show-level person tags.
• If a person has a Nostr identity, include a p tag for their pubkey; person remains optional for RSS compatibility.
• funding - ["funding", "<url>", "<label?>"]
• chapters - ["chapters", "<url>", "<type>"] (e.g. application/json+chapters)
• transcript - ["transcript", "<url>", "<type>", "<language?>", "<rel?>"]
• soundbite - ["soundbite", "<start_seconds>", "<duration_seconds>", "<title?>"] (recommended 15–120s)
• value - ["value", "<type>", "<method>", "<suggested?>"]
• value_recipient - ["value_recipient", "<type>", "<address>", "<split>", "<name?>", "<fee?>", "<customKey?>", "<customValue?>"]
• Example: ["value_recipient", "node", "02d5c1bf8b940dc9...", "40", "Alice (Podcaster)", "false"]
• Example: ["value_recipient", "node", "03ae9f91a0cb8ff4...", "5", "Hosting Provider", "true", "customKey:boost", "customValue:thanks"]
• Grouping: value_recipient tags belong to the nearest preceding value tag. If multiple value tags are present, group recipients by order.

§Mapping guidance (Podcast Namespace → NIP-74 tags)

§Other RSS/iTunes fields (not Podcast Namespace)

These are common in RSS feeds but are not podcast: tags.

• RSS <language> → language
• RSS <guid> (episode) → i tag podcast:item:guid:<guid> (via NIP-73)
• iTunes <itunes:explicit> → explicit
• iTunes <itunes:episodeType> → episode_type

§Notes

• published_at SHOULD reflect the original public release date; created_at reflects when the Nostr event was created.
• Episode events SHOULD include the show GUID (podcast:guid:<guid>) in an i tag when known.

§Discovery

• List shows: filter kinds=[30074]
• List episodes for a show: filter kinds=[30075] with #a=["30074:<pubkey>:<d>"]
• Resolve by external GUID:
• shows: kinds=[30074] with #i=["podcast:guid:<guid>"]
• episodes: kinds=[30075] with #i=["podcast:item:guid:<guid>"]

§Client behavior

• Clients SHOULD render title, summary, and image where available.
• Clients SHOULD prefer imeta audio variants and may fall back to other URLs.
• Comments SHOULD use NIP-22 and reactions SHOULD use NIP-25 with NIP-73 IDs.

§Examples

§Podcast Show

{
  "kind": 30074,
  "created_at": 1737936000,
  "content": "A weekly show about distributed systems.",
  "tags": [
    ["d", "podcast:guid:c90e609a-df1e-596a-bd5e-57bcc8aad6cc"],
    ["title", "Nostr Builders"],
    ["summary", "Interviews with builders in the Nostr ecosystem."],
    ["image", "https://example.com/show-art.jpg"],
    ["r", "https://example.com"],
    ["r", "https://example.com/feed.xml"],
    ["i", "podcast:guid:c90e609a-df1e-596a-bd5e-57bcc8aad6cc"],
    ["t", "nostr"],
    ["t", "technology"]
  ]
}

§Podcast Episode

{
  "kind": 30075,
  "created_at": 1738022400,
  "content": "We discuss relay scaling, spam mitigation, and client UX.",
  "tags": [
    ["d", "podcast:item:guid:d98d189b-dc7b-45b1-8720-d4b98690f31f"],
    ["title", "Episode 42: Relays at Scale"],
    ["published_at", "1738020000"],
    ["a", "30074:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa:podcast:guid:c90e609a-df1e-596a-bd5e-57bcc8aad6cc"],
    ["i", "podcast:item:guid:d98d189b-dc7b-45b1-8720-d4b98690f31f"],
    ["i", "podcast:guid:c90e609a-df1e-596a-bd5e-57bcc8aad6cc"],
    ["duration", "3600"],
    ["season", "4"],
    ["episode", "42"],
    ["t", "nostr"],
    ["t", "scaling"],
    ["imeta",
      "url https://cdn.example.com/episodes/42.mp3",
      "m audio/mpeg",
      "x 3093509d1e0bc604ff60cb9286f4cd7c781553bc8991937befaacfdc28ec5cdc",
      "size 56000000",
      "duration 3600",
      "bitrate 128000",
      "image https://cdn.example.com/episodes/42.jpg",
      "fallback https://backup.example.com/episodes/42.mp3"
    ]
  ]
}