BiznTools
Tools

FOR PUBLISHERS & EDUCATORS

Free calculator widgets for your website.

Turn the numbers in your article, lesson or business guide into a calculation readers can try. Browse 31 free calculators for pricing, cash flow, inventory, work hours and more.

Browse calculators How to add an embed

Free to use. No account. Attribution optional.

One HTML snippetCopy the iframe into your pageA real working calculatorReaders can change the inputsValues stay in the browserNo input uploads or saved scenarios

CALCULATOR LIBRARY

Find the right calculator for your readers.

Open the full tool for its guide and examples, or choose Embed to add the calculation to your own page.

Try the preview
Browse by category

31 calculators across all categories

Business & finance

Price products, explain profit and cash flow, or work through an advertising calculation.

Business & finance

DSO Calculator

Calculate days sales outstanding from receivables, credit sales and the reporting period.

Useful for accounts receivable and working capital lessons.

Use calculator Embed
Business & finance

ROAS Calculator

Calculate return on ad spend and compare it with the contribution needed to cover advertising.

Useful for advertising guides and campaign planning resources.

Use calculator Embed

Inventory & operations

Plan orders, stock and delivery dates, or explain a field, storage or shipping calculation.

Time & pay

Count working days, compare pay and track hours, leave or video timecodes.

PREVIEW & EMBED CODE

Try it here. Add it to your page.

Test the calculator, choose a frame height and copy the HTML when it fits your content.

FREE · NO ACCOUNT OR API KEY

Markup Calculator

Calculate a selling price from cost and markup. See profit and the equivalent margin.

Useful for retail pricing guides and markup lessons.

Open full calculator and guide

Recommended starting height: 1100px. Use 100% width; check the result in your own layout.

Paste into an HTML or embed block. No extra script is needed. You can also select and copy the code manually.

Make it fit your page

Start with a full-width frame in a column at least 320px wide. The height above is a starting point, not automatic resizing. Longer worksheets and results can scroll inside the frame. Check the published page on a phone and desktop, then adjust the height in your editor.

Optional BiznTools credit

Attribution is appreciated, never required. If you want an outer credit, use this simple branded link.

Live preview

Business & finance

Use the calculator below just as your readers would. Its values stay in the frame.

FROM PREVIEW TO YOUR PAGE

How to embed a calculator.

Choose a useful tool, paste its HTML and check the result in your own page.

  1. 01

    Choose the reader’s job

    Put a Markup Calculator beside a price example, a Break-Even Calculator beside startup costs, or EOQ beside an order-quantity lesson. Keep your explanation and assumptions around it.

  2. 02

    Copy into an HTML block

    Select Embed, test the live preview and copy its iframe code. In WordPress, paste it into a Custom HTML block. In another editor, use an HTML or iframe block that permits external frames.

  3. 03

    Check the published page

    Try the example, change a value and tab through the controls. Check both phone and desktop layouts. Adjust the height if a longer worksheet needs more room.

HELPFUL CONTENT, USEFUL CALCULATIONS

Give the answer some context.

An embedded calculator works best beside the question it answers. Explain which values to enter, show your example and let readers compare their own numbers. A pricing guide might pair a markup example with profit margin; an inventory lesson might connect EOQ with a reorder point.

Each embed uses the same calculation method as its full BiznTools calculator. Link to the full tool when readers need the method, assumptions, worked examples or source references.

Inputs have labels and keyboard controls. Keep the iframe title in the code, and check the complete page in your own theme so readers can move between your explanation and the calculator.

What happens to entered values?

Calculations run within the reader’s browser tab. Embed inputs are not transmitted to BiznTools, saved in browser storage, placed in URLs or collected as analytics. No account is required.

Loading an iframe makes ordinary requests for the page and its code; hosting access logs may record those requests. Your own website’s analytics and privacy choices remain outside the calculator frame.

BiznTools privacy How our tools work

BEFORE YOU PUBLISH

Calculator embed questions.

Can I just link to a calculator?

Yes. Use the full calculator link in each card. It takes readers to the working tool with its guide, formulas and examples. An embed is an optional way to offer the calculation inside your own content.

Are these calculator widgets free to embed?

Yes. Articles, courses, teaching materials and business-resource pages can use the calculators here free. You do not need an account, API key or followed backlink. An optional BiznTools credit is available beside the code.

How do I add a calculator to WordPress?

Choose Embed for the calculator you want, then copy the iframe code. Paste it into a Custom HTML block, preview the page and check the published version. Your WordPress setup needs to allow external iframe HTML.

What width and height should I use?

The code uses 100% width. A content area at least 320px wide is a useful starting point. Each calculator has a recommended height that you can adjust in the builder. Longer worksheets can scroll within the frame; check your own layout before publishing.

FREE TO EMBED

Use it where the calculation helps.

Make the calculator part of a useful article, lesson or resource. Attribution is appreciated, never a condition of use.

Need a reference for your explanation? The full tool pages include formulas, checked examples and sources. Any separate editorial citation is your choice.