Redacting a crypto wallet screenshot or video: cover it, then test the file

Hiding a wallet number is easy; keeping it hidden is the hard part. This guide covers the four ways a covered detail comes back, a list of what a wallet screen gives away, device by device steps, a method for video, and the case for building the image instead.

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Hardware wallet app screen composed in Flexdger Wallet: a portfolio named Meridian, a total balance and its change for the day above a row of Transfer, Swap and Buy buttons, the list of holdings with each amount and its move for the day, in a dark theme with a lavender accent.
Composed in Flexdger Wallet. Every figure on it was typed in; nothing is held, sent or received, and no chain is read.

Four ways a hidden number comes back

People rarely fail at redaction because they forgot to hide something. They fail because the thing they hid was only disguised. Four patterns account for most leaks.

Keep those four in mind and the rest of the page is just the procedure that avoids them.

Why a wallet screen gives away more than a bank statement

A support ticket, an accountant's request for a transaction date, a forum thread about a strange token: all ordinary reasons to share a wallet screen. The trouble is that on a bank statement one number is sensitive and the rest is noise. In a wallet, nearly every element is a lookup key into a public ledger. Bitcoin.org's privacy page states that any address's balance and transactions are visible to anyone. Ethereum.org lists what a block explorer shows for a single transfer: the hash, the time, the sender, the receiver, the tokens and the fee. It also mentions that people are often told to use several accounts so assets cannot be tracked easily. One item you forget to cover undoes that separation.

The inventory: what to cover before you send

On the screenWhat someone can do with it
Address, complete or shortenedThe complete one is the account. A shortened one beside an amount and a time leaves only a handful of candidates.
QR codeIt encodes the address. QRcode.com, the site of the inventor's company, explains the error correction that restores data when a code is dirty or damaged, so a half-hidden code may scan anyway.
Transaction hash or explorer linkOne hash opens the whole transaction with both addresses in it.
Exact amount plus timestampTogether they form a search. Rounding the number in your caption does not alter the picture.
Account name, .eth style name, unique avatarEach one points straight at an address or a person.
A rare token or odd mix of tokensEnough to single out one wallet.
Everything around the appNotifications, other tabs, the address bar, bookmarks, lock screen widgets.

A recovery phrase or a private key must never appear in a screenshot, covered or not. Delete such an image everywhere, cloud backups included. Kraken's support pages warn that anyone with remote access to a device can open and copy screenshots and wallet backups.

The procedure, in order

  1. Crop to the minimum. Less picture means fewer things to cover.
  2. Draw solid shapes. A flat fill at 100 percent opacity over every item in the inventory, with some margin, covering the whole line and not just the digits.
  3. Export or recapture. Save a new file, or put the finished image on screen and take a fresh screenshot of it.
  4. Test your own work. Zoom into each box. Open the file in another app. On a duplicate, push brightness and exposure to the maximum; whatever shows was not hidden.
  5. Beware photos of screens. A direct screenshot is cleaner. Apple's personal safety guide notes that photos can carry the location where they were taken, readable by the people you share them with.

Device by device

iPhone

Photos, then the screenshot, then Markup, then Add Shape. Apple's guide lets you choose the fill colour and opacity, so pick a solid fill at full strength. Skip the pen and marker: both have an opacity slider, and the marker has the see-through history noted above.

Mac

Press Shift-Command-4 to capture, then click the thumbnail in the corner to annotate with filled shapes. For a PDF, Preview offers a Redact tool, and Intego points out that the redaction becomes permanent once the file is saved, so keep a spare copy for editing.

Windows

Snipping Tool has a Quick redact feature, but Microsoft's list covers only email addresses and phone numbers. A wallet address, hash or recovery phrase is invisible to it, so cover those by hand. Install updates as well: Microsoft patched the cropped-data flaw in March 2023.

Android

The same bug first appeared in Markup on Google Pixel phones. BleepingComputer reported that roughly 80 percent of an original image could come back, and that anything shared in the five years before the March 2023 fix stays exposed. Update the phone, follow the procedure above and share a fresh capture.

Video: the box has to survive every frame

A screenshot is one chance to get it right; a recording gives you hundreds of chances to get it wrong. The principle is unchanged, an opaque box and no blur, but the workflow differs.

  1. Work on a duplicate and write down every time range with the wallet visible, including the moment the app opens and closes.
  2. Place a solid, full-opacity block over each item. If the phone tilts or the page scrolls, track it or keyframe it.
  3. Start early and end late by a few frames, because transitions are where covers slip.
  4. Look beyond the display: reflections, a second monitor, a tab showing a block explorer, notifications, and your own voice reading an address aloud.
  5. Check the extras: thumbnail, first and last frames, captions, the description and a pinned comment.
  6. Review the exported file, frame by frame at full size, not the editing timeline. If an uncovered version was ever public, delete it; anything already downloaded stays out there.

Automatic tracking and one-tap blur save effort, but scrolling digits, swipes and a hand crossing the display are where they stumble. Use them for a first pass only.

What no box can repair

A flawless cover still leaves context. A screenshot posted on the day of a transfer, with a token and a rounded amount, can be matched to the chain by a patient reader (why redaction is weaker than it looks). The recipient also learns the wallet is yours, which suits an accountant better than a public forum. And the originals remain in the places listed at the top of this page.

When the image is only an illustration, build it instead

Support and tax questions need the real screen, redacted and sent privately. Plenty of images do not: a post about a pump, a tutorial step, a reaction meme, a slide showing what a wallet looks like. There the numbers merely illustrate a point and nothing on screen has to be yours.

For those, skip covering your own wallet. A crypto wallet app simulator, also known as a larp wallet, draws a believable wallet screen from balances you type, holds no funds and never touches a blockchain. A screen made that way has no address to leak, no hash to look up and no original in your camera roll telling another story. There is nothing under the boxes, because there are no boxes. Flexdger Wallet is one such app, a paid one we make (how a larp wallet works). You can try a composed screen in the live demo. For video, the section above still applies to any real footage, and for posts about profits see what one gains screenshot gives away.

Where the line is

Flexdger Wallet is not affiliated with Adobe, YouTube, Apple, Microsoft, Google or Kraken. Their names appear only to describe their rules and tools.

Sources

Questions

Is a solid black box really the only safe way to hide text in an image?

It is the only method that leaves nothing to analyse. Security researchers have shown that pixelated text can be rebuilt, and a see-through marker leaves faint traces of what lies beneath. A fully opaque shape removes the information instead of disguising it.

Why share a new screenshot instead of the edited one?

Some editors have stored pixels you cropped away inside the saved file. A new capture of the finished image contains only what is visibly on screen, so hidden leftovers cannot ride along.

Can a partly covered QR code still be scanned?

Often yes. QR codes carry error correction so they survive dirt and damage, which means a smudge or a blur may not stop a scanner. Cover the entire code with an opaque shape.

What is aCropalypse?

The nickname for a 2023 flaw that let people recover cropped or edited parts of an image saved by Google Pixel's Markup tool (CVE-2023-21036) and by Windows Snipping Tool and Snip & Sketch (CVE-2023-28303). Both were patched that March, but images saved earlier can still hold the data.

How do I hide a wallet address in a screen recording?

Place a solid, fully opaque shape over the whole row for the full time it appears, extend it a few frames either side, track it if the screen moves, and check the exported file at full size instead of the timeline preview.

Can I blur a video after posting it on YouTube?

On a computer, yes: YouTube Studio has a custom blur that can follow an object or stay still. Saved edits cannot be reverted, and an unedited video above 100,000 views may only allow a face blur unless the channel is in the YouTube Partner Program. Copies saved before the edit are unaffected.

Should I redact a screenshot that contains a recovery phrase?

No, delete it. A seed phrase or private key must not exist in an image at all, covered or not. Remove the file, plus any copy in a cloud backup or chat.

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