iPhone Backup Browser is outdated as of November 2017
Please use iBackup Viewer (free, WINDOWS/MAC)

You can download a customized build of iPhone Backup Browser suitable for extraction of ChatStorage.sqlite from latest iOS Whatsapp. It's completely free, open-source and able to extract all your media too

DOWNLOAD iPhone Backup Browser - custom build 16.10.2016

TUTORIAL How to extract ChatStorage.sqlite with iPhone Backup Browser

ChatStorage.sqlite is located at

net.whatsapp.WhatsApp/ChatStorage.sqlite

iphone backup extractor - custom build - step 1

iphone backup extractor - custom build - step 2

wazzapmigrator folder structure

Troubleshooting

If you experience any error (like the one below) please install .NET framework 4.5.1, it's sometimes required on older PCs.

 iphone backup extractor missing .NET

NB: it works on Windows 7 only (errors reported on Windows XP and 8). As an alternative you can try iBackup Viewer (tutorial) or iTools (free)