How to Save Slack, Discord & iMessage Conversations as PDFs on Mac

This guide shows how to save a visible Slack, Discord, or iMessage conversation as a searchable PDF on Mac. You will open the relevant part of the conversation, capture the chat window while paging through it, review the screenshots for sensitive information, and export the selected frames as a PDF.

Only archive conversations you are allowed to retain. Review workplace policy, participant privacy, and any confidentiality requirements before you start.

TL;DR: Open the conversation, use automated Page Down scrolling to capture the chat history, export as a searchable PDF. For sensitive content, redact with Preview.app after export.

Choose what to archive

Choose one channel, direct message, or date range before capturing. Do not archive an entire workspace when the task only requires one decision or project thread. A smaller scope is faster to review and reduces the amount of unrelated personal information in the PDF.

Use the platform's official export or retention tools when they meet the need. Use screenshot capture when you specifically need a readable record of the visible conversation and have permission to retain it.

Capture a Slack conversation

Slack's Mac app (or Slack in the browser) works well with window capture and scroll automation.

Step 1: Navigate to the Conversation

Open Slack and navigate to the channel or DM you want to archive. If you want to capture a specific date range, scroll to the starting point.

Tip for channels with lots of messages: Use Slack's "Jump to date" feature (click the channel name → click the date) to navigate to a specific point in the conversation history rather than scrolling manually.

Step 2: Set Up the Capture

Open Shotomatic:

• Capture mode: Window capture: select the Slack window
• Keypress: Page Down (press the key in the recorder)
• Interval: 800ms

Step 3: Capture the History

Scroll to the oldest message you want to capture. Start the capture. Shotomatic will capture the visible area, press Page Down to scroll forward in time, and repeat.

Important: Slack scrolls chronologically: oldest at top, newest at bottom. Page Down moves you forward in time. Start from the oldest message you want and capture forward to the present.

Stop when you reach the current messages or the end of the range you wanted.

Step 4: Export

Export the selected frames as PDF. The document preserves the visible usernames, timestamps, messages, links, and reactions. If you are deciding between formats, see the broader guide to exporting screenshots as PDF, JPG, PNG, or MP4.

Archiving Entire Slack Channels

For archiving an entire channel (before a workspace gets deleted, for example):

1. Jump to the very beginning of the channel
2. Set up window capture with Page Down at 800ms
3. Start capturing and let it run: this can take a while for active channels
4. Stop at the present

For channels with years of history, consider breaking the capture into chunks: one PDF per month or per quarter. This keeps file sizes manageable and makes it easier to find specific conversations later.

Slack Threads

Slack threads appear in a sidebar panel. To capture a thread:

1. Open the thread in the sidebar
2. Window capture the Slack window (the thread panel will be visible)
3. If the thread is long, use Page Down to scroll through it
4. Export as PDF

Capture a Discord conversation

Discord's Mac app works similarly to Slack for capture purposes.

Channels and DMs

1. Open Discord and navigate to the channel or DM
2. Scroll to the starting point of what you want to capture
3. In Shotomatic, set up window capture with Page Down at 800ms
4. Capture through the conversation history
5. Export as PDF

Discord Server Archival

If you want to archive an entire Discord server (before it's deleted or you leave), you'll need to capture each channel individually:

1. Make a list of channels you want to archive
2. For each channel, scroll to the beginning, capture through to the end
3. Name each PDF: ServerName_ChannelName_Date.pdf

This takes time for large servers. Discord's data export and a screenshot PDF solve different jobs: the export provides structured account data, while screenshots record the visible conversation layout.

Discord Forum Channels

Discord forum channels (the thread-based channels) work slightly differently:

1. Open the specific forum post/thread
2. Window capture with Page Down
3. Each forum thread becomes its own PDF

Handling Embeds and Attachments

Discord messages often include embedded images, link previews, code blocks, and file attachments. Screenshots capture all of these as they appear on screen. Code blocks with syntax highlighting are preserved visually. Attached files show as download buttons: the files themselves aren't captured, only their visual representation.

Capture an iMessage conversation

iMessage (the Messages app on Mac) is a native macOS application, not a web app. Window capture works the same way.

Standard Conversations

1. Open Messages and select the conversation
2. Scroll to the beginning of the section you want to capture (hold Shift and scroll up, or use the scrollbar)
3. In Shotomatic, select window capture and choose the Messages window
4. Press Page Down in the key recorder with 600ms interval (Messages scrolls quickly since content is local)
5. Capture through the conversation
6. Export as PDF

iMessage Quirks

Scrolling to old messages takes time. iMessage loads older messages as you scroll up, which can be slow for conversations spanning years. Be patient: scroll up to your starting point, wait for messages to load, then start capturing downward.

Group chats. Group iMessage chats work the same way. The conversation layout includes all participants' messages with their names, so the PDF is a complete record of who said what.

Tapback reactions. Heart, thumbs up, and other Tapback reactions appear on messages and are captured in the screenshot.

Attachments. Photos and videos shared in iMessage appear inline. Photos are captured at their displayed size. Videos show as thumbnails.

Privacy and redaction

Chat conversations almost always contain private information: real names, phone numbers, addresses, financial details, personal discussions. Before storing or sharing archived PDFs, you should consider redacting sensitive content.

Redacting with Preview.app

Shotomatic captures content but doesn't include annotation or redaction tools. For redaction, use macOS's built-in Preview.app:

1. Open the exported PDF in Preview.app
2. Go to Tools → Redact (or click the redaction tool in the markup toolbar)
3. Select the text or area you want to redact
4. Preview draws a black box over the selected content
5. Save a new copy of the PDF
6. Close and reopen the saved copy to verify that the redacted content cannot be selected, searched, or recovered through the annotation layer

What to Consider Redacting

• Phone numbers and addresses: especially in group chats
• Financial information: account numbers, transaction details
• Third-party personal information: other people's details shared in conversation
• Passwords or credentials: sometimes shared in DMs
• Private personal discussions: if you're archiving a work channel, personal side conversations may not belong in your archive

Consent and Ethics

Before archiving conversations, consider the other participants:

• Workplace chats: Check your company's data retention policies. Some organizations have rules about exporting Slack messages.
• Private conversations: The other person may not expect the conversation to be permanently archived. Use good judgment.
• Group chats: Multiple people's messages are captured. Consider whether everyone would be comfortable with their messages being archived.

This isn't a legal guide: use your own judgment about what's appropriate to save and store.

Organize the chat archive

Naming Convention

Platform_Contact-or-Channel_DateRange.pdf

Examples:

• Slack_engineering-decisions_2026Q1.pdf
• Discord_StudyGroup_General_202603.pdf
• iMessage_JohnDoe_20260101-20260322.pdf
• Slack_project-alpha_Thread-DeploymentPlan.pdf

Folder Structure

Chat Archive/
├── Slack/
│   ├── WorkspaceName/
│   │   ├── Channels/
│   │   └── DMs/
├── Discord/
│   ├── ServerName/
│   │   └── Channels/
├── iMessage/
│   ├── Individual/
│   └── Groups/

Searchability

PDF export includes OCR automatically. This turns your chat archive into a searchable document instead of a folder of images. Looking for that deployment configuration someone shared in Slack three months ago? Search "nginx config" in Finder and find it instantly: even though the original Slack message is past the 90-day limit.

If your archive starts as screenshots, the same principle applies to other capture-heavy workflows: searchable PDFs make saved screenshots easier to find later.

Improve the chat captures

Start from the right point. Don't capture an entire five-year conversation if you only need the last three months. Scroll to the relevant starting point before beginning capture.

Use a consistent window size. Keep the chat application at a consistent window width across captures. This makes the PDFs uniform and easier to read.

Capture during low-activity periods. If the channel is actively being used while you capture, new messages will appear during the process. For the cleanest capture, choose a quiet time.

Close sidebars and panels. In Slack, close the channel details sidebar. In Discord, close the member list. This gives the chat area maximum width and makes the most of each captured frame.

Check the scroll direction. Slack and Discord show newest messages at the bottom. When you start capturing from an older point, Page Down scrolls you toward newer messages. Make sure you're scrolling in the right direction.

Break long archives into manageable chunks. A year-long Slack channel might produce a 500-page PDF. Consider splitting by month or quarter for easier navigation.

FAQ

Does Slack's free plan delete messages?

Slack access and retention depend on the current workspace plan and retention settings. Check the Slack Help Center and your workspace configuration for the current limits.

Can I export my full Slack or Discord history through the app?

Slack workspace owners can request a full export, but individual users on free plans cannot. Discord has a data request option but it returns your own messages in raw JSON, not readable conversations. Screenshot capture gives you the visual conversation as it appeared.

How do I handle private or sensitive information in chat captures?

After exporting to PDF, open the file in Preview.app and use the redaction tool to black out sensitive information. Shotomatic captures content but doesn't have annotation features: use Preview.app for redaction.

Will the PDFs include images and emoji shared in chat?

Screenshots record the visible text, emoji, images, link previews, and reactions. Animated GIFs appear as a single captured frame, and attachments are represented by whatever is visible in the chat window.

Can I search through my saved chat archives?

PDF export can add an OCR text layer. Search results depend on image quality, typography, and layout, so verify important names, dates, and quotations in the exported file.

What about voice and video call content?

This guide covers text chat only. Voice and video calls aren't captured by screenshots. For call recordings, you'd need separate recording software with appropriate consent from all participants.

Save the conversation

Run a short test first, then review every frame before export. For recurring workplace archives, use a schedule that matches your retention policy instead of capturing entire workspaces by default.

Download Shotomatic or see pricing.