All endpoints
Substack Note Details

Substack Note Details API

Get a Substack Note by URL or ID, with its replies. Returns the note text, author, date, likes, replies and restacks, any quoted post or note, and the reply thread nested to any depth.

Price: $0.003 per request
Free tier: 50 requests/month
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Endpoint
GET /v1/substack/note

Parameters

url
Note URL, e.g. https://substack.com/@hamish/note/c-355659691 (max 500 characters). Provide either url or note_id.
note_id
Numeric note ID, with or without the c- prefix. Provide either url or note_id.
get_sentiment
Set to true to add AI emotion analysis (Plutchik's Wheel) to each result. Adds +$0.001 per request to the cost. Returns emotion scores, dominant emotion, intensity, and polarity.

Response fields

note
The note
note_id
Note ID
body
Note text
date
Date and time posted (UTC)
author
Author's handle
author_name
Author's display name
author_id
Author's user ID
author_url
Link to the author's profile
source
"Substack"
domain
"substack.com"
likes
Number of likes
replies
Number of replies
restacks
Number of restacks
reactions
Reaction counts by emoji
author_pic_url
Author's profile picture URL
author_bestseller_tier
Author's bestseller badge tier: 0, 100, 1000 or 10000
lang
Language code
attachments
Media and quoted items. Each has type (image, video, link, post, note, publication) and url, plus title or dimensions where relevant
publication
The author's primary publication
url
Direct link to the note
sentiment
Emotion analysis results. Only present when get_sentiment=true. Returns null if analysis fails.
emotions
Plutchik emotion scores (0-100) for: joy, trust, fear, surprise, sadness, disgust, anger, anticipation.
dominant_emotion
The emotion with the highest score.
emotional_intensity
Overall emotional intensity on a scale of 0-10.
polarity
Overall sentiment polarity: positive, negative, or neutral.
replies
Replies to the note, each with the note fields plus replies_list (nested replies)
count
Number of top-level replies returned

Example Request

curl "https://apidirect.io/v1/substack/note?url=https%3A%2F%2Fsubstack.com%2F%40hamish%2Fnote%2Fc-355659691"   -H "X-API-Key: YOUR_API_KEY"

Example Response

{
  "count": 5,
  "note": {
    "attachments": [
      {
        "attachments": [
          {
            "post_id": "218085342",
            "publication": "On Substack",
            "title": "Model Behavior: George Saunders",
            "type": "post",
            "url": "https://on.substack.com/p/model-behavior-george-saunders"
          },
          {
            "duration": 44.6,
            "height": 1280,
            "type": "video",
            "url": "https://substack.com/api/v1/video/upload/c7e75333-51e0-4895-9c1c-597fbbdb5d11/src",
            "width": 720
          }
        ],
        "author": "arielleswedback",
        "author_name": "Arielle Swedback",
        "body": "@George Saunders spoke about Substack and our AI conversation yesterday on Late Night with Seth Meyers. Grateful to him for helping us see our way through",
        "note_id": "355302724",
        "type": "note",
        "url": "https://substack.com/@arielleswedback/note/c-355302724"
      }
    ],
    "author": "hamish",
    "author_bestseller_tier": 0,
    "author_id": "3567",
    "author_name": "Hamish McKenzie",
    "author_pic_url": "https://substack-post-media.s3.amazonaws.com/public/images/46d05a58-6aa7-4896-bd79-5972793b5d4f_1179x1179.jpeg",
    "author_url": "https://substack.com/@hamish",
    "body": "Still feels like a massive honor just for @George Saunders to be publishing on Substack, let alone be speaking of it on the big shows. ",
    "date": "2026-10-08 04:48:40",
    "domain": "substack.com",
    "lang": "en",
    "likes": 53,
    "note_id": "355659691",
    "publication": "Disjointed",
    "reactions": {
      "❤": 54
    },
    "replies": 5,
    "restacks": 3,
    "source": "Substack",
    "url": "https://substack.com/@hamish/note/c-355659691"
  },
  "replies": [
    {
      "attachments": [],
      "author_id": "1347124",
      "author_name": "Emma Gannon",
      "author_url": "https://substack.com/profile/1347124",
      "body": "v cool! Can’t wait to read your book Hamish 👓",
      "date": "2026-10-08 06:13:37",
      "domain": "substack.com",
      "lang": "en",
      "likes": 1,
      "note_id": "355689719",
      "publication": "The Hyphen by Emma Gannon",
      "replies": 0,
      "replies_list": [],
      "restacks": 0,
      "source": "Substack",
      "url": "https://substack.com/home/post/c-355689719"
    }
  ]
}

Frequently asked questions

Where do I find note IDs?

In the note's URL (the c-123456 part) or in the note_id field of User Activity items.

How does pricing work?

You only pay for successful requests. The Substack Note Details API costs $0.003 per request. There are no monthly fees or commitments. You get 50 free requests per endpoint every month.

Do I need a credit card to start?

No. You can sign up and use the free tier (50 requests/endpoint/month) without adding a payment method. You only need to add a card when you want to exceed the free tier.

Are there rate limits?

Yes, there's a concurrency limit of 10 simultaneous requests per endpoint per user. If you need more, just get in touch.

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