How to download/transfer whatsapp chat data, photos, videos etc. on sd card?

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Go to phone storage there you find a folder name of Whatsapp in the end copy that folder and paste that folder in Memory card. Simple :)

Step 1: Open ES File Explorer on your Android mobile or even some default File Manager on your phone. In case if you don’t have any File Manager, download ES File Explorer from here.
Step 2: Open the internal storage files.In the internal or device storage, you will find a folder named WhatsApp.
Step 3: Under the WhatsApp folder, you will find a folder named Media. Now cut the Media folder.

Step 4: Now go to SD card and create a folder named WhatsApp and paste the media files into it.