uCoz

This plug-in provides an opportunity to automatically integrate calculator. This way you don’t need to place the code manually, all you need to do is authorize access from the uCalc account and choose an already made calculator from the list.
<a href="https://ucalc.pro" rel="nofollow ugc">uCalc</a> is a service that helps you create and maintain calculators to estimate services and delivery costs as well as build booking, review, feedback, and event registration forms. No special knowledge and operational fees are required. You can create a calculator by just dragging the blocks and putting together simple formulas like A+B=C. You are provided with the embed code that needs to be added to a website powered by any platform. The built-in calculator is edited through the service.
The builder has the following benefits:
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Ready-to-use templates and a collection of elements: a slider, button, drop-down list, checkmarks, contacts collection, date picker, etc.
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Completed orders notifications are sent to the owner or manager of the website via email or SMS
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Results with the opportunity to apply a promo code are sent to clients via email or SMS
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Design customization: background and text colors, fonts and color customization of the elements
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Display of several results, for example, with and without a discount
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Recognition of any currency and measure (weight, size, volume, product unit)
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Option to illustrate every element
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Widgets on the website automatically adapt for smartphones and tablets
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Check out the video to learn how to add a calculator with the help of the plugin: 
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/m_Usz8NP_RU?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>

uCalc

Create a costs calculator by simply dragging blocks, adding pictures and texts. It takes only 10 minutes, $0, and no special knowledge!

niftyflowrocks

Niftyflow is a drag-and-drop form and calculator builder that enables you to easily create highly customizable form and calculator widgets. 
This plugin allows you to easily embed widgets created with our builder into your WordPress website using shortcodes.
<h3>Demo</h3>
Try a demo of our easy calculator builder for free <a href="https://niftyflow.rocks" rel="nofollow ugc">on our website</a> – instant access, no signup required.
<h3>Requirements</h3>
The plugin requires a niftyflow account. You can sign up for free at <a href="https://niftyflow.rocks" rel="nofollow ugc">niftyflow.rocks</a>.

Niftyflow – Form & Calculator Builder

Create multilingual price quote, ROI, and finance calculators with drag & drop. Easy to embed on any website. No developer or coding skills required.

uCalc vs Niftyflow – Form & Calculator Builder