Block-based visual hiding
Useful for faces and backgrounds, but small blocks may preserve recognizable details.
010 · IMAGE EDIT
Image Mosaic & Blur Tool
Hide faces and private information with mosaic, blur, or solid redaction.
LOCALPROCESS IN YOUR BROWSER
WORKSPACEImage mosaic and blur workspace
Drop an image here
Your image is processed only in this browser and is not uploaded to a server.
JPG, PNG, WebP · One image at a timeHOW TO USE
How to use
- 01
Select or paste an image.
- 02
Choose Rectangle or Freehand Brush.
- 03
Choose mosaic, blur, or solid redaction.
- 04
Set strength, brush size, or redaction color.
- 05
Mark every area that should be hidden.
- 06
Move or adjust areas and compare original and result.
- 07
Zoom in and check for visible private information.
- 08
Choose format and quality, then download.
PRIVACY REDACTION GUIDE
Mosaic, blur, and solid redaction
Use fully opaque solid redaction first for sensitive text that must not be recovered.Soft visual obscuring
Preserves visual tone, but weak blur may leave text and numbers readable.
Preferred for sensitive data
Recommended for account numbers, card numbers, addresses, and other sensitive text.
EXPERT POST
Practical criteria for safe image redaction
Selection accuracy, export resolution, overlaps, edges, and final zoom inspection directly affect safety.Prefer solid redaction for sensitive text
Blur and mosaic make content harder to recognize, but they are still visual obfuscation. Use fully opaque black or white redaction for IDs, account numbers, card numbers, passwords, verification codes, and detailed addresses. Covering the complete information matters more than matching the surrounding background color.
Use different tools for faces, plates, and documents
A freehand brush is practical for irregular shapes such as faces, while rectangles are more accurate for license plates, ID numbers, addresses, and chat lines. Do not cover only the eyes or a few digits. Include enough surrounding detail to prevent identification from remaining features.
Cover beyond the visible edges
Selecting exactly on text or plate edges can leave pixels visible in the full-resolution export. Small gaps between brush strokes may also become visible after zooming. Extend the area slightly beyond the sensitive content and inspect overlaps for broken edges.
Judge strength at source resolution
A weak blur or small mosaic block may look sufficient in a reduced preview but still reveal letter strokes, number shapes, or facial features in the source-size export. Check at 100% before downloading, then increase strength or switch to solid redaction when details remain.
Understand quality tradeoffs
Very large mosaic blocks can destroy the surrounding visual structure, while excessive blur can spread into nearby content and reduce image quality. Apply effects only where needed. Accurate selection usually preserves the image better than simply increasing the effect across a larger area.
Manage many areas in a clear order
For chats and documents, add separate areas for names, phone numbers, addresses, order numbers, and account details. Independent areas are easier to move, revise, or delete without restarting. When areas overlap, verify that the final rendering order produces the expected result.
Zoom before editing on mobile
Fingers can cover small text on a phone. Pinch to zoom and position the image first, then use one finger for the rectangle or brush. Brush size is based on image coordinates, so recheck the actual covered area whenever the zoom level changes.
Choose output format with transparency in mind
PNG and WebP can preserve transparency, while JPG cannot. A chosen background color is applied when exporting transparent images to JPG. JPG or WebP often suits photos, while PNG is useful for document captures, logos, and transparent artwork. Recheck edges after changing format.
Balance output quality and file size
Lower JPG or WebP quality reduces file size but can introduce artifacts around small text and redaction edges. Avoid extremely low quality for public documents or evidence images. PNG is lossless, so its output may be larger than the original even when the edit is simple.
Use a repeatable final inspection
Switch to the result view, hide editing outlines, and inspect the four corners and center at 100%. Search again for names, phone numbers, addresses, dates, order IDs, and account details. Only the areas you selected are processed; the tool does not automatically discover missed information.
What local processing means
The image stays in the current browser session and is not uploaded to a server. The original may still remain in your photo library, downloads folder, or cloud-sync service. This tool creates an edited copy; it does not delete or manage the original file.
Continue with related tools carefully
Crop or rotate first when you only need part of the image, then use compression or resizing after redaction when a smaller public file is required. Cropping or enlarging later can make edges look different, so inspect the final publish-ready file once more.
FAQ
Frequently asked questions
01Are images uploaded to a server?+
No. Images are processed only in your browser.
02Does it detect faces automatically?+
No. You select every area manually.
03Which is safer, mosaic or blur?+
Neither guarantees complete removal. Use solid redaction for sensitive text or numbers.
The original file is unchanged. Refreshing or resetting removes the current edit.