Compress Image for WhatsApp

WhatsApp already compresses photos you send in a chat, and you don't get a say in how much. If you've compressed a photo yourself and the app squeezes it again, the two rounds of loss add up. So for pictures where quality matters, send the file as a Document instead. WhatsApp leaves documents as they are, and compressing first keeps that document small.

For everyday photo sends, a smaller file still goes out faster when you've got one bar of signal on a train, and it uses less of your data pack. In a big family group that adds up, because everyone downloads what you share.

For normal chat photos, compressing to 500KB is a good balance. If it's a picture people will want to keep or print, go up to 1MB or 2 MB and send it as a Document.

JPG is selected by default because every phone opens it without trouble. WebP files are smaller, but a WebP sent as a Document can be awkward for some people to open or save to their gallery, so JPG is the easier choice for sharing.

When you send a photo as a regular image, WhatsApp may resize and recompress it. When you send it as a Document, it arrives as the exact file you picked, same name and size. That's why compressing first helps: a 6 MB original sent as a Document costs the receiver 6 MB of data, while a 1MB copy looks almost the same and downloads far quicker.

The compression runs on your own device and the photo is never uploaded to a server, so nobody else gets a copy before it reaches your chat. Camera details like GPS location aren't kept in the new file either, which is a small privacy win if you're sharing a photo taken at home.