Highly recommended. Read why…

(For the free version)
First of all, I want to tell you that I have used ALL the booking calendars that exist in WordPress until today. And all had serious flaws in their free versions and moreover they were a bit expensive for what they offered in their paid version.
So I ended up using this one; luckily.

Pros (that most of the rest don’t have):
1) Customer support. As you will read below I had an issue with another plugin. Karen responded my email the same day and for a week was trying to find a solution. Who does that for someone who uses the free version??
2) Is very simple and easy to use. It has a very nice and totally year calendar.
3) The hours are also presented well and neatly. There is a setting with which you can set the duration of the booking to be independent of the booking hours. For example, you can set the duration to 60′, but the customer can book 10:00 or 10:10 or 10:50 etc. You don’t find this in another booking plugin.
4) The free version includes only a couple of fields (“e-mail”, “single line” and “terms and conditions”) but unless you need a very special field the “single line” can be renamed in anything you want!
5) You can block specific dates and hours.
6) Uses captcha verification. Not reCaptcha but still…in the free version it’s a big deal.

Cons:
1) It conflicts with “NavMenu Addon for Elementor” (if you use it).
2) The style is simple and you cannot change it unless you use CSS (you can’t edit it in Elementor but use the website’s CSS in the edit options). For me it was just the width of the fields.

Moreover, I will suggest my clients to buy the paid version. Is very cheap for one website and has everything; form builder with many fields and options and countless addons for integrations with other plugins, payments, notifications etc.