Post Engagement API
Four endpoints cover who engaged and how: the comments on a post, the reactions on a post, the reactions a person has left, and an engagement summary for a post.
Each comment and reaction carries the profile behind it, which is what makes this an audience list rather than a counter. Pipe those profiles into the profile endpoint and an engaged audience becomes an enriched one.
- requests served per month
- 40M+requests served per month
- uptime
- 99.9%uptime
- median response time
- 1smedian response time
- serving production traffic since
- 2023serving production traffic since
What you send, what you get
A post URL or URN. For profile reactions, a professional profile URL.
- Comments
- text, date, reactionCount, replies, commentUrn
- Reactions
- reactionType, reactionsByType, totalCount
- The person behind each one
- name, headline, publicIdentifier, url, imageUrl
- Paging
- paginationToken, hasMore
GET /api/v1/post/comments · /post/reactions · /profile/reactions · /post/engagement. Full field reference in the documentation.
One call, start to finish
Request
curl "https://api.fetchin.io/api/v1/post/comments?url=https://www.linkedin.com/posts/activity-7364..." \
-H "X-API-Key: your-api-key"Response
{
"comments": [
{
"text": "This matches what we saw rolling it out last quarter.",
"date": "2026-08-15T11:04:00.000Z",
"reactionCount": 12,
"profile": {
"name": "Dana Whitfield",
"headline": "VP Engineering at Northwind",
"publicIdentifier": "danawhitfield"
}
}
],
"paginationToken": "..."
}What teams build with it
Audience capture
Take the people who engaged with a relevant post, whether it is yours or a competitor post, and turn them into a list with names, roles and employers attached.
Intent signals
Someone commenting on a post about a problem you solve is a warmer signal than anyone on a bought list, and it is timestamped.
Event and launch follow-up
After an announcement, pull everyone who reacted or commented and route the ones that match your ICP straight to a rep.
Community research
Read the actual replies under a post to learn the objections and vocabulary of a market, rather than guessing at them.
Why this endpoint
- Every comment and reaction carries the profile behind it, so the output is a list of people rather than a count
- reactionsByType tells you which reaction was left, not just how many there were
- Replies come back nested under their parent comment instead of flattened into the same stream
- Token-based pagination that reflects what is really there, so an empty page means empty rather than broken
- Feeds straight into the profile endpoint, which is how an engaged audience becomes an enriched one
Walkthroughs that use it
Each of these takes one job end to end, with the flow and the code.
Questions
- Can I get the people who reacted, not just the count?
- Yes. The reactions endpoint returns a profile for each reaction, with name, headline and public identifier, alongside which reaction type was left. The count on its own is available too, from the posts endpoint.
- Are replies to comments included?
- Yes, replies are returned nested under the comment they answer, so a thread keeps its structure and you can tell a reply from a top-level comment.
- How do I enrich the people who engaged?
- Each engagement carries a public identifier. Pass it to the profile endpoint and you get the full record: role, employer, seniority and history. That two-call pattern is the most common way these endpoints are used.
- How does pagination work?
- Every response carries a token for the next page. Paging is token-driven rather than offset-driven, so pass the token back rather than incrementing a start index.
The rest of the API
Try it on your own data
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