You can save your chat history by sending your conversations via email.
- Go to the WhatsApp main screen.
- Click on Options > Settings > Chat History > Send chat history.
- Select the chat you want to email.
- Your chat history will be attached to the email as a .txt file that you can send.
Note: There is a limitation of sending only 10,000 messages at one time.
Also, it is not possible to restore your chat history from this exported .txt file. Read this article for instructions on how to restore your chat history.
WhatsApp Support Team