Fixing location data in photos

MarsEdit developer Daniel Jalkut had a great post recently about protecting privacy by stripping out location information from a photo’s metadata before uploading it to your blog:

If you choose to publish photos in your blog posts, it’s important to understand that image metadata may reveal more to your blog’s readers than you necessarily intended.

We followed up on this for Core Intuition episode 409 and again briefly on episode 411. also tries to strip out location information, but a couple of times it has been applied inconsistently because there are several different ways to get a photo in to I’ve found and fixed a new bug related to this and want to document it here.

The native iOS and macOS apps for have always fixed the orientation information in a photo and stripped any metadata before uploading. The web version of also did the same thing on the server when using the Uploads tab. But I noticed a case where this processing was skipped when attaching a photo to a new post on the web and not uploading it separately in the Uploads tab or with a third-party app.

As a precaution I’ve decided to retroactively strip metadata from existing photos that have been uploaded over the last few years. I wrote some scripts to check these photos, updating both our primary photo storage and the published blogs that were affected.

I also stripped metadata from any profile photos that contained location information. In some cases, the colorspace may have changed. If you notice any subtle changes to your profile photo and want to re-upload it, you can do that under Account.

I’m sorry I missed this. If you have any concerns, let me know via You can also check one of your photos by downloading it from your blog and opening it in an app that can display metadata. (In for macOS, choose Tools → Show Inspector.)

Manton Reece @manton