đź–¤ How to Properly Redact Sensitive Info from Images [Standalone Guide]

IT & Systems
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:black_heart: How to Properly Redact Sensitive Info from Images [Standalone Guide]

Black boxes aren’t enough if you skip the metadata

:locked::framed_picture::shield::scissors:

You’ve got a screenshot with sensitive data. Maybe it’s a support ticket, a config file, or something you need to share but can’t show everything. So you draw a black box over it and call it done.

Not so fast. That black box might not be as solid as you think. And even if it is, the image itself can still leak info through metadata.

Here’s how to do it right.

:artist_palette: Redacting with MS Paint (Windows)

MS Paint is free, simple, and gets the job done. Here’s the process:

  1. Use Snipping Tool to create a screenshot

  2. Copy or open the screenshot in MS Paint

  3. Select Fill in the toolbar and set it to solid color

  4. Select a color for Color 1 and Color 2 (black works, or pick an agreed-upon color)

  5. Select the Square/Rectangle tool

  6. Use the magnifier in the bottom right corner to make it easier to see all text

  7. Draw a rectangle over each piece of text that needs to be redacted (repeat for each piece)

  8. Save as JPG to remove any layering. Do not save as PNG.

Why JPG? JPG compression flattens and reprocesses the image data. Some advanced editors (Photoshop, Fireworks) can save PNG files with hidden layers that could be recovered. JPG eliminates that risk entirely and also strips out any potential compression artifacts from the original.

:warning: Don’t Forget the Metadata

Here’s what most people miss: images contain hidden data called metadata. This can include:

  • Date and time the image was taken

  • Device info (camera, phone model)

  • GPS coordinates (if location was enabled)

  • Software used to edit the image

  • Sometimes even thumbnails of the original image

AI tools can pull metadata from images to potentially recover redacted info or identify the source. If you’re sharing something sensitive, strip the metadata too.

:window: Removing Metadata on Windows (Built-in)

  1. Right-click the image file and select Properties

  2. Go to the Details tab

  3. Click Remove Properties and Personal Information

  4. Select “Create a copy with all possible properties removed” or choose specific fields

  5. Click OK to create a clean file

That’s it. No extra software needed.

:red_apple: Removing Metadata on Mac

Mac doesn’t have a one-click option like Windows, but here are your choices:

Screenshot Method (Quick but lossy)

  • Take a screenshot of the image. This strips metadata but reduces quality.

Preview Export Method

  • Open the image in Preview

  • Export as PDF

  • Convert back to JPEG

  • Metadata is removed in the process

Third-Party Tools

:penguin: Removing Metadata on Linux

Linux users can use ExifTool from the command line:


# View metadata

exiftool image.jpg

# Remove all metadata

exiftool -all= image.jpg

Simple and effective.

:books: Additional Resources

:brain: TL;DR

  • Use solid rectangles to redact text in MS Paint (or similar)

  • Save as JPG, not PNG, to flatten layers

  • Remove metadata before sharing. Windows has this built-in. Mac and Linux need extra steps.

  • Metadata can leak info like location, device, and timestamps

  • AI can sometimes recover redacted info from metadata or improperly flattened images

:speech_balloon: Your Turn

Have you ever shared an image and realized later it had sensitive info in it?

What tools do you use for redacting screenshots?

Any tips for handling this in a team environment?

Drop a comment below!