What to Check Before You Post a Photo

Ranked by how much damage it does, not by how often it is mentioned. The right-hand column is the honest bit.

Two things surprise people. The first is how much of a folder carries coordinates: in a 90-file test folder spanning six formats, 75 files had a GPS latitude, including the video clips. Video is the one nobody checks, and compressing it does not help. A test clip re-encoded 14.8% smaller still reported its full shooting-location record.

The second is the serial number. It is not secret, it is not sensitive on its own, and it is the most reliable way to prove that two accounts belong to the same person.

Some do, some do not, and the ones that do can stop. We went through this service by service with evidence and confidence levels in stripping GPS from photos before you share them. The short version:

• Signal and Mastodon strip, and both have shipped source or release notes saying so explicitly.
• WhatsApp strips when you send a photo as a photo. Sending it as a document preserves the file intact, checksums and all, which is exactly what the “send as document for better quality” advice costs you.
• Flickr, Google Photos, email attachments and AirDrop from Finder all preserve it. Flickr’s setting is called hide EXIF, and hide is the correct word.
• Instagram, Facebook and LinkedIn are not verified. All three sit behind login walls, there is no primary source, and everything written about them in 2026 is repetition of older repetition. We are not going to guess on your behalf.

That last bullet is the reason this article exists in the shape it does. If your safety depends on a platform doing something, and you cannot check that it does, then you do not have a safety measure. You have a habit.

Strip locally. Then the answer is the same on every service, including the ones that change their pipeline next quarter without announcing it.

Five steps. The first two cover almost everything; the last three are the ones that catch the cases that matter.

1. Look before you delete. One command tells you what is in the folder, which is worth knowing before you decide it does not matter.

exiftool -csv -r -GPSLatitude -GPSLongitude -DateTimeOriginal \
  -Model -SerialNumber -Artist ~/Desktop/to-post/ > inventory.csv

That took 543 ms for 90 files and opens in Numbers. If you only want the short version, exiftool -r -if '$gpslatitude' -p '$filename' ~/Desktop/to-post/ prints one line per file that still has coordinates.

2. Strip everything, not just the GPS. Point one process at the folder. Keep the color profile, because otherwise your photos shift hue on other people’s screens, and keep the orientation or your portraits go sideways.

exiftool -overwrite_original -all= \
  -tagsfromfile @ -Orientation -icc_profile \
  -r -ext jpg -ext heic -ext png ~/Desktop/to-post/

Ninety mixed files took 4,030 ms. Afterwards, EXIF, GPS, IPTC and XMP tag counts across the folder were all zero. For the reasoning behind each flag, see our exiftool reference for macOS; if you would rather not use Terminal at all, removing EXIF data on Mac compares six routes including Preview and Photos.

3. Clear the extended attributes. This one is macOS-specific and almost never mentioned. A file you downloaded carries the URL it came from in an attribute beside the file, not inside it, so no metadata tool touches it.

xattr -c ~/Desktop/to-post/*

We verified this directly. Running exiftool -overwrite_original_in_place -all= on a tagged file removed all 39 EXIF tags and left the “Where from” URL fully readable. Plain -overwrite_original happens to drop it, because it writes a new file, but that is a side effect rather than a guarantee. xattr -c is the deliberate version, and it also clears Finder tags, which can be their own disclosure.

4. Rename. IMG_4471.HEIC is fine. A filename containing a client, a person, a project codename or a date is not, and it travels with the file into every download folder the picture ever lands in.

5. Look at the photo. Not at the metadata — at the picture. House number, street sign, school uniform, vehicle registration, the view out of the window, the reflection in the glass, the boarding pass on the table. This is the step no tool performs and the one that most often matters.

Four things, in increasing order of how uncomfortable they are.

The crop that is not a crop. If you crop a photo and the tool copies the original tags across, the embedded thumbnail comes with them, and that thumbnail is still the uncropped frame. We measured it: after cropping a 4,032 × 3,024 image down to 1,200 × 900 and copying the tag set over, the extracted thumbnail was byte-for-byte identical to the original’s, the same 2,997 bytes with the same SHA-256, showing the whole original frame at 160 × 120. Check it yourself:

exiftool -b -ThumbnailImage cropped.jpg > thumb.jpg && open thumb.jpg

Stripping fixes this, because the thumbnail lives in the EXIF. Cropping does not.

Documents are a different problem. A PDF keeps author names in the Document Info dictionary, in an XMP packet, in every comment and markup annotation, and in the previous versions left behind by incremental saves. Nothing removes the comment authors automatically, and exiftool does not actually delete anything from a PDF at all — a single command puts it all back. The full version is in removing metadata from a PDF on Mac.

Redaction is not metadata. A black rectangle drawn over a name in Preview leaves the text underneath selectable and searchable. No metadata tool addresses this, and people conflate the two constantly.

The pixels locate you anyway. This is the one that changed the shape of the problem. Current image-geolocation models work from the picture alone, with no metadata of any kind, and they are good enough that a clean file taken outside a recognizable building is still a located photo. We went through what these systems can and cannot do, and what actually reduces the risk, in why stripping EXIF is no longer enough.

None of that makes stripping pointless. It makes it the floor rather than the ceiling. Coordinates are exact and a model’s guess is not, so removing them still removes the most precise thing in the file.

Run the same read you ran at the start. Anything that prints is still in the file. The -a matters, because exiftool hides duplicate tag names by default and you want to see all of them.

exiftool -a -G1 ~/Desktop/to-post/photo.jpg

A clean JPEG shows the JFIF header and, if you kept it, the ICC profile. A clean HEIC will still report 25 ICC and 25 container tags no matter what you do, because exiftool cannot remove the profile from a HEIF container even though it prints a warning claiming it did. Neither block identifies anything.

Two reads people forget. xattr photo.jpg lists the extended attributes, and anything beyond com.apple.provenance is yours to clear. And for video, exiftool -a -GPSPosition -Title -Artist clip.mp4, because a phone clip carries coordinates exactly like a photo does and nobody ever checks.

For one photo before one post, exiftool -all= photo.jpg is free, takes four seconds, and produces a file whose compressed image data is byte-for-byte identical to the original. On a folder, one exiftool process beat our own app by roughly 3.8× in timed testing. Our strip operation is exiftool with a bundled binary, and the output on a single JPEG has been measured byte-identical to it.

If you will not open Terminal, Preview’s Remove Location Info handles the case most people actually care about, also for free. It removes the GPS block and nothing else, which is worth knowing before you rely on it.

We make Smol, and it earns its place in a narrow set of cases:

• This has to happen every time, by habit, through a Finder right-click or a watched folder rather than a command someone has to remember.
• The originals must survive automatically, because you are doing this at speed and under pressure.
• You are stripping and resizing and converting in the same drop, before the batch goes out.
• Somebody else on the team has to do it and is never going to install Homebrew.

And the cases where nothing here is the right tool. If you are at genuine risk from what you post, metadata removal is a hygiene step, not a protection strategy, and you should be reading advice written for that situation rather than a file-utility guide. If you need a documented chain of custody, you need a procedure with hashes at every step. If you need words removed from a page, you need redaction.

Smol is $29 once. The step-by-step version is in our help article on removing EXIF and GPS data, and what EXIF data actually contains walks a real tag dump line by line if you want to know what you are deleting before you delete it.