Manatee

A privacy checklist for files you share from a Mac

· 7 min read

Before a file leaves your Mac, run through five checks: the filename, the visible content, the metadata inside the file, the extended attributes beside it, and the channel you are sending through. Most files need only a minute. The checks below give the built-in Mac tool for each step, and Manatee’s Clean mode where a batch is involved.

The one-minute checks for any file

These apply to every file, every time.

  1. Rename it. Screenshot 2026-08-23 at 10.14.52.png and Contract v7 FINAL (legal edits).docx both say something. Give the file a neutral name before it goes out.
  2. Open it and look. Open the actual file you are about to send and confirm it is the version you mean. Sending the wrong copy is the most common leak of all.
  3. Check the inside metadata. Press Command-I in Preview for photos and PDFs; File > Properties in Word; mdls in Terminal for anything. The post on how-to-check-a-file-s-metadata-on-a-mac.html covers each tool.
  4. Decide whether the channel sends the file or a copy. Email and AirDrop from Finder send the exact file. Messaging and social apps re-encode and drop some metadata, unpredictably. Never rely on the channel to clean anything.

Photos, screenshots and videos

Photos

What leaks: GPS coordinates, device model, capture date and time, and software version. The picture itself can leak a location through windows, house numbers, reflections, and paperwork.

  1. Open the photo in Preview and press Command-I. A GPS tab means it has coordinates.
  2. For one photo, click the GPS tab and Remove Location Info, then save.
  3. For a set, drop them on Manatee’s Clean mode, which strips GPS and camera EXIF and writes cleaned copies alongside the originals.
  4. Look at the frame for visible identifiers, and crop or reshoot if needed.
  5. If you share from the Photos app, click Options in the share sheet and switch Location off each time.

More at how-to-remove-gps-location-from-photos-on-a-mac-before-sharing.html.

Screenshots

What leaks: the filename’s timestamp, and everything on screen: your name in menus, the Wi-Fi network, notification banners, tabs, the Dock, and whatever is behind the window.

  1. Capture a single window (Shift-Command-4, then Space) instead of the whole screen.
  2. Turn on Do Not Disturb first.
  3. Redact with an opaque rectangle in Preview’s Markup, never the highlighter, and never blur for text.
  4. Export as a new PNG or JPEG so the shapes are flattened.
  5. Rename the file.

Screenshots have no GPS; the content step is the whole job.

Videos

What leaks: GPS, device make and model, software version, and the creation time, all in the container. Plus the picture and the audio.

  1. Check with mdls in Terminal (look for kMDItemLatitude and kMDItemAcquisitionModel) or ffprobe if ffmpeg is installed.
  2. Strip with Manatee’s Clean mode, or with Photos (Image > Location > Remove Location, then export), or with ffmpeg -i in.mov -map_metadata -1 -c copy out.mov.
  3. Watch it through for visible identifiers and names said aloud.
  4. Delete any sidecar files a camera wrote next to the clip (.THM, .SRT, .LRV).

Documents: Word, Excel, PowerPoint and PDF

Word, Excel and PowerPoint

What leaks: creator and last-saved-by names, revision number, editing time, template path, and any tracked changes or comments still in the file, whether or not they show on screen.

  1. Set Review > Tracking to All Markup and look at what is there.
  2. Review > Accept > Accept All Changes and Stop Tracking (reading what you accept).
  3. Review > Delete > Delete All Comments in Document.
  4. Word > Preferences (or Settings) > Security, and check “Remove personal information from this file on save.”
  5. File > Save As, with a neutral name.
  6. Verify by renaming a copy to .zip, opening it, and checking that word/comments.xml is absent and docProps/core.xml has an empty creator.

If the recipient only needs to read, export a PDF with the view set to No Markup. The post on track-changes-and-comments-can-leak-cleaning-a-docx-before-you-send-it.html has the full walkthrough.

PDFs

What leaks: Title, Author, Subject, Keywords, Creator, Producer, and dates. A PDF made with Print > Save as PDF gets your account name as Author unless you change it in the save dialog. Images placed in a PDF keep their EXIF.

  1. Open in Preview, press Command-I, read the General tab.
  2. Strip the author and revision fields with Manatee’s Clean mode, or reprint the PDF through Print > Save as PDF with the Author field emptied.
  3. If the PDF contains a redaction, zoom in and make sure it is opaque and flattened, not an annotation sitting over intact content.

Audio files, and the metadata beside a file

Audio

What leaks: title, comments, encoder, recording date, embedded artwork with its own EXIF, and in store-bought tracks the purchaser’s name and email.

  1. Check with mdls or ffprobe.
  2. Blank the standard fields in the Music app (select the track, Command-I), or strip everything with ffmpeg -i in.mp3 -map_metadata -1 -c copy out.mp3.
  3. Rename the file, since voice memo names can be generated from your location.

Manatee’s Clean mode does not cover audio tags; it is built for photos, PDFs, and Word documents. Use Music or ffmpeg for audio.

Extended attributes and archives

macOS keeps some metadata beside a file rather than inside it: Finder tags, comments, and kMDItemWhereFroms, the URL a download came from. None of it goes by email or web upload. It can go by AirDrop and inside a zip made in Finder.

  1. Run mdls on the file and look for kMDItemWhereFroms.
  2. Before AirDropping or zipping, clear the attributes with xattr -c followed by the path in Terminal.
  3. Clean files before zipping; a zip preserves everything inside each file.

Cleaning a batch with Manatee

For a folder of mixed photos, PDFs, and documents, Manatee’s Clean mode handles them together: it strips GPS, camera EXIF, and document author and revision metadata, and writes a cleaned copy beside each original, which is never modified. Drop files on the window, on the menu bar icon, or right-click in Finder and choose Fix with Manatee under Services.

Everything runs on the Mac: no uploads, no account, and the only network call is a license check. The first 24 hours are free with every feature; after that it is $9 once.

What it does not do: redact visible content, accept or reject tracked changes for you, edit audio tags, or remove a name typed into the body of a document.

The final check before sending

  1. Open the exact file you are attaching. Not the original, the cleaned copy.
  2. Command-I in Preview (photos, PDFs) or File > Properties in Word. Confirm the fields are empty and there is no GPS tab.
  3. Read the filename once more.
  4. If the channel matters, send it to yourself first and inspect what arrives.

The whole routine is under two minutes for a photo and under five for a document with history.

Questions

Is there a single tool that cleans everything?

No. Metadata lives in different places in different formats, and visible content has to be handled by eye. Manatee covers photos, PDFs, and Word documents in one pass; the Music app or ffmpeg cover audio; Preview’s Markup covers redaction.

Does compressing a file into a zip protect its metadata?

No. A zip stores each file exactly, metadata included, and a Finder-made zip adds extended attributes on top. Clean first, then compress.

If the platform strips metadata, why clean before uploading?

Because the upload itself delivers the original to the platform, because some platforms and all “send as file” options pass it through, and because you cannot predict where a file goes after the first recipient. Cleaning at the source is the only step you control.