Redact a Social Security Number From an Image
A nine-digit SSN is the one number that turns a screenshot into an identity theft problem. Covering it with a blur is not enough — the digits have to be painted out of the file itself. This page is about doing that in a browser, with no upload step.
Free, no account, and the image never leaves your browser.
Why an SSN in an image is different from other redactions
Most things people hide in a screenshot — a username, an order total, a chat message — are embarrassing or commercially sensitive. A Social Security number is different. It is a permanent identifier that cannot be changed, and it is one of the three pieces of data used to open credit in someone else's name. There is no rotation, no reset, no new password.
The risk is compounded by where SSNs actually appear. They turn up on tax forms, payroll stubs, benefits letters, medical intake sheets, background check results, and — most often — in screenshots that someone took to ask a question. A person photographs a W-2 to ask an accountant about a line item, or screenshots a pay stub to prove income to a landlord. The number rides along in the corner of the frame.
A second problem is that SSNs are short. Nine digits fit in a small area of a screenshot, and small areas are exactly where a low-strength blur fails. If the block size of a pixelation or the radius of a Gaussian blur is tuned for a face, the digits of a nine-digit number stay legible at the original resolution.
What to cover on a page that shows an SSN
The number itself is the obvious target. The surrounding fields are what make it usable, and they are usually overlooked.
- The nine digits in any format
- 123-45-6789, 123 45 6789, and a bare 123456789 all appear on real documents. Cover every instance, including ones in footers or page numbers that look like unrelated digits.
- Full legal name
- An SSN on its own is hard to use. An SSN printed next to a name is a complete identity credential, so the name has to go too.
- Date of birth
- Often printed directly above or below the SSN on tax and payroll documents. It is the third leg of the identity stool.
- Employer ID (EIN)
- Appears on W-2 and 1099 forms. It is not your SSN, but it identifies your employer and is not something to publish.
- Account and routing numbers
- On a direct deposit section, these are printed near the SSN. They let someone move money, not just borrow in your name.
- Barcodes and QR codes
- Some payroll systems print a barcode that encodes the employee record. It survives a redaction of the text field and is easy to miss.
What the built-in detection will and will not find
Auto-detect runs a text recognition pass in your browser, then matches the recognized text against patterns. It is genuinely useful here because an SSN has a fixed shape, but it is a starting point, not a guarantee.
Found automatically
- The separated form 123-45-6789
- The space-separated form 123 45 6789
- Multiple SSNs on the same page
Needs a box by hand
- A bare run of nine digits with no separators. The tool deliberately does not treat every nine-digit number as an SSN, because doing so would flag invoice numbers, phone extensions, and dates.
- Handwritten numbers, and digits in fonts that the recognition pass reads as letters.
- Numbers that are rotated, curved, or printed over a colored background.
- Digit groups split across two lines by a page break.
- Any SSN that is part of a longer string of digits, such as a reference number with the SSN embedded inside it.
Removing the number, step by step
The whole flow takes under a minute for a single screenshot, and nothing is stored between visits.
Open the image
Drop a PNG, JPEG, or WebP onto the page, paste it with Ctrl/Cmd+V, or choose a file. The image is decoded in the tab; it is never sent anywhere. Files up to 25 MB and 40 million pixels are accepted.
Run auto-detect, then read its output critically
Auto-detect will usually find the separated SSN. Look at each box it draws before trusting it. If the number on your document is written without separators, expect it to be missed and plan to draw the box yourself.
Draw a box with margin on every side
Drag a box that extends past the digits on all four sides. Tight boxes are the most common cause of a leaked digit — the characters at the edge sit half outside the fill.
Keep the fill on solid black
Solid black is the default and the only style recommended for an SSN. Pixelate keeps the shape of the original characters, and the digits of a nine-digit number are short enough that a mosaic can leave them guessable.
Cover the second copy
If the same number appears twice on the page, cover it twice. Detection reports each occurrence separately, and it is easy to scroll past the second one.
Download and re-open the PNG
The export is a new PNG drawn on a fresh canvas at the original resolution. Open the downloaded file and zoom in on each covered region before you send it.
Why a solid fill and not a blur
A blur and a solid fill look similar in a thumbnail and behave completely differently in the file. A blur is a filter: it averages neighboring pixels and writes the averaged result. The information is degraded, not removed, and short strings of large characters are exactly the case where degraded information is often still readable — either directly at high zoom, or by someone who knows what the number is supposed to look like and can check candidates against the checksum.
A solid fill replaces the pixel values inside the box with an opaque color. The original pixel data is not averaged, transformed, or pushed into another channel — it is overwritten in the destination canvas. The exported PNG contains the fill color and nothing underneath it.
There is a related mistake worth naming, because it is common in presentation software and design tools: placing a black rectangle on top of an image without flattening. The rectangle is a separate object, and the text underneath is still in the file. Exporting from a flattened canvas avoids that class of error entirely, which is why this tool rebuilds the image from scratch instead of layering a shape over the original.
The pixelate option exists for layouts where you want the document to remain recognizable — a form where the reader needs to see that a field existed. It paints an opaque black base first, then a downsampled mosaic on top, so nothing shows through. But the mosaic is built from the original pixels at reduced resolution, which means it is weaker than solid fill for short strings. For an SSN, use black.
Frequently asked questions
- Is it enough to cover just the last four digits?
- No. The last four digits are the ones routinely used for verification, and a partial SSN is still a partial credential. Cover the entire number.
- Does the exported file still contain the original EXIF data?
- The export is a new PNG encoded from a canvas, and EXIF lives in the original file container rather than in pixel data, so camera and GPS fields from the source file are not carried over. Re-encoding also means the original file's metadata structure does not survive.
- Can I undo a box I drew in the wrong place?
- Yes. Undo is available as a button and as Ctrl/Cmd+Z, with redo on Ctrl/Cmd+Shift+Z. Clear all removes every box at once, and Start over loads a different image. Because the edit is live in the page, nothing is written to disk until you download.
- Does it work on a phone?
- Yes. You can open the page on a phone or tablet and draw boxes with a finger. On touch screens a Draw/Scroll switch is available, because a tall screenshot needs to be scrollable and a draw mode that swallows every drag makes that impossible.
- What if the number is on a photo of a paper form?
- That works, but expect the recognition pass to be less reliable on a photograph than on a screenshot. Shadows, perspective, and print quality all reduce accuracy. Draw the boxes by hand and check the result at full zoom.
- Do you keep a copy of the image?
- No. There is no upload step, no server-side processing, and no storage. The image is decoded in the tab, and if you reload the page it is gone.