Save Slack messages and threads as PDFs

Slack to PDF for messages, threads and channels. Save a conversation as a clean, readable PDF record automatically with Zapier, Make or n8n.

Quick answer. Pick a trigger, like adding a certain emoji to a message. Your automation collects the message or thread, puts it into a template, html-pdf.com turns it into a PDF, and the PDF is posted back to Slack or saved to your drive.

What you'll build

React to a message with a page emoji and get a PDF of the whole thread a few seconds later. Save every decision posted in #approvals as a dated PDF. Send a client a tidy copy of a shared channel conversation at the end of a project.

The PDF shows names, times and messages in a clean layout, without the Slack sidebar and buttons a screenshot would include.

What you need

• A Slack workspace where you can add apps.
• Zapier, Make or n8n, connected to Slack.
• A design. The report template works well as a wrapper. A template is a ready made page design, so you only change the text.
• An API key from html-pdf.com. You get 100 free pages once, with no card.

Step by step with Zapier (single message)

1. Trigger. Create a Zap with Slack and the event New Reaction Added. Choose the emoji, for example page_facing_up.
2. Make the PDF. Add Webhooks by Zapier → Custom Request. Method POST, URL https://html-pdf.com/v1/pdf.
3. Headers. Authorization with Bearer hp_live_... and Content-Type with application/json.
4. Data. Paste the JSON below and map the message text, author, channel and time.
5. Deliver. Add Slack → Send Channel Message with the url, or Google Drive → Upload File to keep a copy.

{
  "html": "<h1>#approvals</h1><p><b>Priya Shah</b> 10 Oct 2026, 15:42</p><p>Approved the Q4 budget at 48,000 EUR. Go ahead with the vendor contract.</p>",
  "filename": "approval-2026-10-10.pdf",
  "response": "url"
}

The url is a download link that works for 24 hours, so save the file somewhere if you need it for longer. See the Zapier guide.

Step by step with n8n (whole thread)

Threads have many replies, so n8n or Make is the better fit.

1. Trigger. Add a Slack Trigger node listening for reactions, or a Schedule Trigger for a daily channel export.
2. Get the replies. Add an HTTP Request node calling Slack's conversations.replies with the channel and the message ts, using your Slack credentials.
3. Build the page. Add a Code node that turns each reply into a block with the name, time and text.
4. Make the PDF. Add an HTTP Request node posting to https://html-pdf.com/v1/pdf. Set the response format to File.
5. Deliver. Use the Slack node to upload the file to the thread, or save it to Google Drive.

The same flow in Make uses Slack → Make an API Call and HTTP → Make a request. See the n8n guide and Make guide.

Code path for developers

With a Slack bot token that can read history, a thread export is a short script.

const { messages } = await (await fetch(
  `https://slack.com/api/conversations.replies?channel=${process.env.CHANNEL}&ts=${process.env.THREAD_TS}`,
  { headers: { Authorization: `Bearer ${process.env.SLACK_TOKEN}` } }
)).json();

const body = messages.map(m => {
  const time = new Date(Number(m.ts) * 1000).toLocaleString("en-GB");
  return `<div style="margin-bottom:12px"><b>${m.user}</b> <small>${time}</small><p>${m.text}</p></div>`;
}).join("");

const r = await fetch("https://html-pdf.com/v1/pdf", {
  method: "POST",
  headers: { Authorization: `Bearer ${process.env.HTML_PDF_KEY}`, "Content-Type": "application/json" },
  body: JSON.stringify({ html: `<h1>Thread export</h1>${body}`, format: "A4", response: "url" }),
});
console.log((await r.json()).url);

Messages include user IDs. Look up names with users.info if you want full names in the PDF.

Ask your AI agent

Connect the html-pdf.com MCP server to an assistant that can read Slack.

Read the thread about the vendor contract in #approvals and use html-pdf to make an A4 PDF record. Show each message with name and time, and add a short summary of the decision at the top.

FAQ

Can I export a whole Slack channel to PDF?

Yes. Use conversations.history instead of conversations.replies, and run it on a schedule. Long channels may become many pages, and each page costs one credit.

Will images and files from Slack appear?

Slack files need a login, so they will not load by link. List them by name in the PDF, or download them in your automation and include them as data links.

Do I need admin rights?

You need permission to add an app or connect Zapier, Make or n8n. The app can only read channels it has been added to.

Is my conversation stored by html-pdf.com?

No. Your HTML is not stored, and download links expire after 24 hours.