Why WhatsApp photos look blurry, and when to shrink them first
A photo that looks sharp in your gallery can look soft after it is sent on WhatsApp. That is expected: the app recompresses pictures it sends as normal photos to save data, so you lose detail whether you want to or not.
What happens to a normal photo
Modern phone photos are several megabytes. WhatsApp resizes and recompresses them before sending. Fine texture, small text and thin lines suffer first. If the picture was already compressed, for example a screenshot saved as JPG, the second round stacks new artifacts on top of the old ones.
When to send as a document
If quality matters, such as a contract page, a receipt or a design, use the attach menu and send it as a document. The app then sends the original file untouched. The trade-off is size: the file can be many megabytes, which is slow on weak mobile data.
When to shrink it yourself
If the connection is poor or the recipient only needs to see the content, JPG Compressor for WhatsApp reduces each photo to about 1 MB by lowering quality and, when needed, dimensions. You control the result instead of leaving it to the app, and it uploads much faster. For a specific size or quality, use Image Compress & Resize instead.
Practical tips
Photos of text hold up better with light compression than with small dimensions, because letters need pixels. Avoid re-sending the same compressed image repeatedly. Keep the original on your phone; the shrunk copy is only for sharing.
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