We have found one software suitable in our database for this conversion.
You can use programs and websites like Whatsapp Xtract or WhatCrypt tools to export the chat backups from WhatsApp Messanger (.crypt files) and save them as in a HTML format (.htm, .html) which when viewed using a web browser will look exactly like your WhatsApp.
For the later versions of CRYPT format, like CRYPT12, you first need to use some tool that converts crypt12 to crypt, before you can work with them further, as the higher versions are heavily encrypted.
CRYPT
Files with crypt extension are most likely best known as chat history backups made from WhatsApp messaging app.
HTM
A htm file extension is used for web documents stored in HTML Hypertext Markup Language file format. HTML language provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes and other items. Its the main language for writing web pages. A htm web page can be displayed in any Web browser.