mdoff

It’s not a standalone plugin requires installed Contact Form 7
This plugin solves problem of e.g. email verification or email confirmation.
Just create second field with <code>_confirm</code> at the end of the field name. Look in the screenshots for example.

cf7 Confirm Field

Plugin allows to make sure that e.g. emails in two fields are the same

Mário Valney

<a href="https://wordpress.org/plugins/contact-form-7/" title="Install it first, of course" rel="ugc">Contact Form 7 (CF7)</a> is a awesome plugin used by 1+ million WordPress websites.
But even it allow users to use HTML instead of just Plain Text email it’s not trivial to users who aren’t developers create something really pro.
However, time to leave all your worries behind! As a recently launched “Contact Form 7 – HTML Mail Template Extension” will allow you, WordPress developers or not, to use a simply but beautiful HTML Template in your CF7 so users will get better emails than just amount of text.
<h4>Configurations</h4>
Easily and quickly! No configurations required to start, but you can change a lot of stuff like colors, header image and width (by now… new versions will come).
<h4>Email Template</h4>
The plugin applies a HTML template to email sent from your CF7. The Template is optimized to show your HTML emails perfectly in the most popular email browsers including mobile ones.

HTML Template for CF7

Improve your Contact Form 7 emails with a HTML Template.

cf7 Confirm Field vs HTML Template for CF7