FrameShotHow to Blur or Redact Sensitive Information in Screenshots
Why blur and pixelation can sometimes be undone, when to use a solid redaction box, and a checklist of details to hide before you share a screenshot.
Shahriar AhmedDeveloper of FrameShot4 min read
Screenshots leak more than people expect: an email address in a corner, a customer’s name in a sidebar, an access token in the address bar. Covering them up is easy, but not every way of covering them actually hides them. Here is what to look for before you share, the real difference between blurring, pixelating and redacting, and how to do it properly.
What to check before you share
Look over the whole image, not just the part you meant to show. These are the details that slip through most often:
- Personal details: names, email addresses, phone numbers, home addresses and profile pictures.
- Secrets: passwords, API keys, access tokens, recovery codes and one-time codes.
- Money: card numbers, bank details, account balances and invoice amounts.
- Codes you can scan: QR codes and barcodes on tickets, boarding passes and parcels.
- The edges of the screen: notifications, chat previews, other open tabs and your bookmarks bar.
- Addresses in the URL bar: links that contain session IDs, tokens or email addresses.
- The file name: it may contain the page title or the website’s name.
Blur, pixelate or redact: what’s the difference?
Blur smears each pixel into its neighbours. Pixelate replaces squares of the image with their average colour. Both make content hard to read at a glance, but both keep some information about what was there. For short pieces of text in a known format, like a card number, a date or a short code, that can be enough to work backwards: open-source tools such as Depix have recovered pixelated text from screenshots, and researchers have shown the same for blurred faces and text.
A solid redaction box replaces the pixels completely. There is nothing left to recover, because the original content is no longer in the image.
| Method | Good for | Can it be undone? |
|---|---|---|
| Blur | Faces, backgrounds, long passages you only want to soften | Sometimes, for short text |
| Pixelate | The same, with a more obvious look | Sometimes, for short text |
| Solid box | Passwords, numbers, codes, anything secret | No |
Rule of thumb: if it would be a problem for someone to read it, use a solid box. Use blur when you only want to keep the viewer’s attention elsewhere.
How to redact a screenshot with FrameShot
- Capture the page with FrameShot, or import an existing image into the library.
- Open it in the editor and pick Blur, Pixelate or Redact (solid) from the toolbar.
- Drag over the area to hide. Adjust the blur strength, the pixel block size or the box colour in the side panel. You can move or resize the area at any time.
- Export. When you download, copy or save as PDF, the effect is flattened into the pixels of the new file. The hidden content does not exist in what you share.
FrameShot keeps your original capture in the library so you can change your mind later. When even your own copy shouldn’t contain the hidden details, choose Apply edits permanently in the editor’s menu to replace the original.
Common redaction mistakes
- Using a highlighter or a see-through shape. A semi-transparent box only tints the text. Make sure the cover is fully opaque.
- Covering text in a document editor. Drawing a black rectangle over text in many PDF or document editors leaves the text underneath, where it can be selected and copied. Redact the image itself, or use a tool that removes the text.
- Trusting a crop to delete things. In 2023 a bug known as “aCropalypse” showed that some phone and desktop screenshot tools left the cropped-away part of the image inside the saved file. Exporting a fresh image, as FrameShot does, avoids leftovers like that.
- Hiding it once, showing it twice. The same name often appears in a header, a tab title and a sidebar. Check every copy.
- Forgetting the file name. FrameShot names files from a template that can include the page title and the website. Rename the download if the name gives something away.
What about screen recordings?
Hiding things in a video afterwards is much harder than in a screenshot, so plan before you press record:
- Share a single tab instead of your entire screen, so notifications and other apps stay out of the video.
- Turn on Do Not Disturb so message previews don’t pop up.
- Use a demo account or test data rather than real customers.
- Close tabs and windows you don’t need, and hide your bookmarks bar.
If something private still slips into a recording, save that frame as a screenshot in FrameShot’s player, redact it, and share the screenshot instead, or record that part again.
