A screenshot often shows more than the message you meant to share: contact names, email addresses, phone numbers, profile pictures, links with private tokens. This tool reads the screenshot on your device to suggest boxes, covers them with solid blocks, and writes a new file, avoiding the 2023 bugs where cropped screenshots kept the hidden part inside the file.
What screenshots give away
Screenshots are the way people share proof: a funny message, a rude reply, a receipt, an error, a confirmation code. Because they capture the whole screen, they also capture everything around the point you are making:
- Chats: the other person's name and photo, their number if they are not in your contacts, names of other group members, message previews from other chats.
- Email: sender and recipient addresses, CC lists, signatures with phone numbers and job titles, the subject lines of other emails in the list.
- Social apps: usernames, profile pictures, follower counts that make an account easy to find, comments from people who never agreed to be shown.
- Banking and shopping: account numbers, card digits, balances, order numbers, delivery addresses.
- The browser: the address bar (password-reset links, shared-document links and some session links contain secret tokens), other open tabs, bookmark names, the profile picture of the signed-in account.
- The phone itself: notification banners from other apps that appeared at the wrong moment.
Cropping deals with the edges. Anything in the middle of the screen needs covering.
Redact a screenshot step by step
- Take the screenshot as usual, then bring it here: file button, drag and drop, or on a phone, your photo library.
- Press Find text. The page reads the screenshot locally and boxes the email addresses, phone numbers, card and account numbers and QR codes it recognizes. The first time, it downloads its reader from this site and shows the size first.
- Box what the reader cannot know is private: names, usernames, profile pictures, addresses, order and account numbers, the address bar, other tabs.
- Make sure Cover with still says Solid block. Text under Pixelate or Blur can be pieced back together.
- Press Export, look over the copy at full size, and save or share it.
How the text finding works
Find text runs an OCR engine (Tesseract) inside your browser to turn the screenshot into words with positions, then applies simple rules:
- Email addresses: anything shaped like
name@example.com. - Phone numbers: runs of digits with the lengths and separators phone numbers use, with or without a country code.
- Card numbers: groups of 13 to 19 digits that pass the Luhn checksum used by payment cards, which filters out most order numbers and timestamps.
- IBANs and other long numbers: international bank account numbers (checked with their built-in check digits) and any run of eight or more digits, which catches many account, customer and ID numbers.
- QR and other square codes: found by a barcode reader (QR, Data Matrix, Aztec and PDF417), since a code can carry a link, a Wi-Fi password, a ticket or a payment address.
Screenshots are the best case for OCR: sharp, straight, high-contrast text. Small or light-gray text, text on photos, emoji-heavy names and unusual fonts can still be missed or misread. Treat the suggestions as a head start and look over the whole image before exporting.
Why pixelated text in screenshots is a known weakness
Screenshot text is rendered in a handful of standard system fonts at standard sizes, which is exactly what reconstruction tools need. Depix, published as a proof of concept in 2020, recovers text from screenshots that were pixelated with a simple box filter by generating candidate text in the same font, pixelating it, and matching the blocks. Its author notes the approach fails when the image is compressed afterwards, but you should not count on that. A solid block leaves nothing to match.
The cropped-screenshot bugs of 2023
Two widely used screenshot editors once leaked the parts you removed:
- Google Pixel's Markup editor (CVE-2023-21036, "aCropalypse"): after cropping or marking up a screenshot and saving over the original, the file was not shortened, so data from the original image stayed after the end of the new one. Tools appeared that recovered part of the cropped-out area. Google fixed it in the March 2023 Pixel update.
- Windows Snipping Tool and Snip & Sketch (CVE-2023-28303): the same mistake on Windows 10 and 11, fixed by Microsoft in 2023.
Screenshots made and shared before those fixes can still carry the leftover data. Running them through this tool gives you a new file without that leftover: export paints only what is visible onto a new canvas and encodes a new image, so trailing data from the old file has nowhere to come from.
What changes in the exported file
- Every box becomes an opaque black block, merged into the pixels.
- The hidden data of the original file does not come along. Screenshots carry less metadata than camera photos, but some include the device model, software and creation time, and edited screenshots may carry an editor's notes or leftover data as described above. None of it is copied.
- The resolution stays the same. Very tall scrolling captures appear scaled down in the editor (to roughly 2,048 px top to bottom) but are saved full size; when a browser cannot build an image that tall, the saved copy is scaled down to 4,096 px in height and the page mentions it.
Supported screenshots
- PNG, JPEG and WebP, which is what phones and computers save screenshots as. HEIC screenshots open in Safari; other browsers ask you to convert them first.
- Works in current Chrome, Edge, Firefox and Safari on Windows, macOS, Linux, Android, iPhone and iPad.
- Long scrolling screenshots work; very tall ones are where the size fallback may kick in.
- Not supported: screen recordings (video).
Where the screenshot goes
It stays in your browser. Opening it reads the file into the tab; the OCR and barcode readers run in the tab; the finished copy waits in memory until you download it. Pressing Find text for the first time pulls the readers' program files from this site; those requests carry no part of your screenshot. Close the tab and the page's copies are gone.
Technical details
The OCR engine is tesseract.js with English language data, and square codes are found with ZXing compiled to WebAssembly; both are hosted on this site at fixed versions. The editor maps boxes from the preview back onto the original pixels, then encodes a new image. To see for yourself that no request carries your screenshot, follow the developer tools walkthrough.
FAQ
What should I hide in a chat screenshot?
Names and profile pictures of everyone except you (unless they agreed), phone numbers, other chats' previews, and anything in a message that identifies a third person, like an address or workplace.
Does Find text catch names?
No. Names cannot be told apart from ordinary words by rules alone, so box them by hand. Find text covers email addresses, phone numbers, card numbers, IBANs, long digit runs and QR-type codes.
Can someone recover text I covered?
Not if you used Solid block: the exported file contains only the block. Pixelated or blurred text in screenshots is a known target for reconstruction tools.
Is cropping enough?
Cropping removes the edges, and in a buggy editor even that could leak. Here, export always writes a new file from what is visible, so leftovers from an earlier crop, or anything you covered, cannot hide inside it.
Does the OCR upload my screenshot?
No. Recognition happens inside your browser with an engine fetched from this site; the screenshot itself goes nowhere.
Why redact the address bar?
Links for password resets, shared files and some sign-ins carry secret tokens in the address. Anyone who can read the full link may be able to open it.
Sources
Checked 2026-10-11.
- CVE-2023-21036 in the National Vulnerability Database: the Pixel Markup truncation flaw.
- CVE-2023-28303 in the National Vulnerability Database: the Snipping Tool flaw.
- Depix, a proof of concept for depixelizing screenshots: method and its stated limits.
Last updated: