How to Use PhantomBuster to Collect LinkedIn Post Commenters

The short answer: if your LinkedIn post asks readers to comment a keyword to get a guide, PhantomBuster's LinkedIn Post Commenters Export turns those comments into a spreadsheet at about 20 seconds per 10 comments, so a post with 500 comments uses 16 minutes 40 seconds of the 20 hours on the $69-a-month Start plan (automation page, pricing page, checked on 26 October 2026). The steps: connect your LinkedIn session, give the Phantom the post's URL, switch on watcher mode so repeat runs fetch only new comments, schedule a daily launch while the post is live, have your assistant filter the results for the keyword, and send the guide once a person has checked the list.

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Before the post goes up:

1. Run time against the trial. For example, 500 comments need 500 / 10 x 20 = 1,000 seconds. The trial's 2 hours, 7,200 seconds, would cover that seven times, but the pricing page caps trial exports at 10 rows, so the list itself needs a paid plan.
2. What you already have. The post, the guide you promised, and a CRM. The Phantom adds nothing to that except the list of names, which is the tedious part.
3. The count that says it worked. Commenters who wrote the keyword, against all commenters, then guides delivered, then replies to the guide. Write the first number down after day one.

PhantomBuster's own store page describes this as a lead-magnet workflow. Plans and the wider product are in the PhantomBuster glossary entry.

What you need

• A PhantomBuster account; the trial is enough to test the setup, Start or above to export the list.
• The post's URL, or a Google Sheet of URLs shared with anyone who has the link.
• The PhantomBuster browser extension in the browser where you are signed in to LinkedIn.

Two rules sit above any setting. The Phantom works through your own LinkedIn session cookie, and section 8.2 of LinkedIn's User Agreement bars scripts and crawlers that scrape or copy profiles and other data from LinkedIn, so the account at stake is the one you connect. And commenters gave their names to your post, not to your sales database: the Dutch data protection authority's guidance on scraping (in Dutch, April 2025) says a legal basis is needed even for data anyone can see online, and that for a business the only realistic one is usually legitimate interest, which scraping often struggles to meet. Sending someone the guide they asked for is one purpose. Adding them to an outbound sequence is another, and it needs its own basis.

Step 1: Connect your LinkedIn session

Open the LinkedIn Post Commenters Export, click Use now, and link your LinkedIn session through the extension in one click, or paste the session cookie by hand. The extension also supplies your browser's user agent, which the Phantom needs, per the tutorial on the automation page. Keep the browser updated; an expired cookie stops the runs.

Step 2: Point it at the post

Paste the post's URL into the input. For several posts, use a Google Sheet shared with anyone who has the link; the Phantom reads column A unless you name another column. Uploading a CSV of URLs works only on paid plans.

Step 3: Set volume, replies and watcher mode

Set how many comments to process per launch, and whether to include replies to comments. Then switch on watcher mode: on repeated runs it fetches only comments that are new since the last one, which is what a post collecting comments over several days needs. Under the result file, list the fields to keep (profile link, first name, comment text) so the export holds no more personal data than the job uses. Do not rename the file between launches; a new name restarts processing from the beginning.

Keep the volume modest. The automation page recommends at most 50 posts a day from a regular LinkedIn account and 100 with Sales Navigator, and for highly engaging posts it suggests 10 comments a day, rising to 50. It also asks you not to run other LinkedIn Phantoms at the same time.

Step 4: Schedule the runs

Choose a recurring launch, daily while the post is still drawing comments, rather than one big run at the end. Each launch takes one of your plan's slots while it works; Start has 5. Results appear in the Results tab, ready to download as CSV or JSON or to send to Google Sheets, and in your Leads list.

Step 5: Let an assistant filter for the keyword

Connect PhantomBuster's MCP server to Claude: under Customize, Connectors, add https://mcp.phantombuster.com as a custom connector, then sign in to PhantomBuster and pick the workspace, as the MCP documentation describes. No API key is needed.

Ask it to pull the latest results from the commenters export and build a filtered lead list of people whose comment contains your keyword, leaving out your colleagues and current customers by name. The MCP can launch Phantoms, read their output and create or update filtered lists in the selected workspace. A person then opens that list and reads every row before anyone receives anything: a comment that says "GUIDE please, the company already pays for a competitor" is a different conversation from "GUIDE".

Step 6: Deliver the guide, then decide who becomes a lead

PhantomBuster's suggested workflow chains the export to an invitation accepter and a message sender. Send the guide yourself, or from your outreach tool, to the checked list instead; a guide that arrives as a personal message from the author reads as one. Move only the people who answer the guide into your CRM, through the HubSpot, Salesforce or Pipedrive integration on the integrations page or a CSV import.

What PhantomBuster's pages warn about

• Very long threads. Posts with tens of thousands of comments may not load in full; the automation extracts what LinkedIn loads, often the most recent.
• Trial limits. No CSV input, exports cut at 10 rows, no JSON or download links.
• Running out of time. When execution time is spent, automations pause until it resets or you upgrade, per the pricing FAQ.

The routine the store page recommends

For a post with a few dozen comments, skip the tool: open the post, copy the names of everyone who wrote the keyword into a sheet, and send the guide by hand. It takes less time than the setup above, and it costs nothing.

Past that size, read the automation page's advice with the plan page beside it. It tells you to run the export daily and to chain it with Auto Connect and the message sender, and every scheduled run and every chained Phantom draws on the same execution hours and slots. The habit the page recommends is also the path from Start's 5 slots to Grow's 15.

FAQ

Can it capture people who liked the post?

Yes, through a separate Phantom, the LinkedIn Post Likers Export. The commenters page notes that commenters usually show more intent, because they took the time to write.

How long does a run take?

About 20 seconds per 10 comments, replies included, per the tutorial on the automation page.

Will I get every comment on a very popular post?

Not always. On posts with 10,000 or more comments, the tutorial on the automation page suggests several launches or watcher mode to collect what it can.