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What WhatsApp does to your image

WhatsApp re-compresses images when you send them as a photo, and the result is often noticeably soft — particularly for large images with fine detail. The more you make it compress, the worse the output, because its encoder is working on a file that has already been through one lossy pass.

Higher-resolution sends happen when you use the document attachment option rather than the photo option, which bypasses most of the re-compression at the cost of the recipient seeing a file rather than a picture.

Getting a better result

• Resize to around 1600 pixels on the long edge before sending — WhatsApp targets roughly that scale anyway, so pre-resizing on your terms looks better than letting it happen on theirs.
• Compress lightly (quality 85 or so) rather than heavily. A heavily compressed image that WhatsApp then compresses again looks much worse than a lightly compressed one.
• For anything where quality matters — a document, an ID, a design proof — send it as a document attachment, or send a link.
• Strip location metadata if you would rather not share where the photo was taken.

Status and profile pictures

Status updates and profile photos are cropped and scaled aggressively, typically to a square. A square source image, resized to about 1000 × 1000 pixels before uploading, avoids the awkward cropping that happens when a wide photo is forced into a square frame.