<!-- wp:html --> <div data-ct-calc="tip"></div> <script src="https://calculatethis.net/widget.js" async></script> <!-- /wp:html -->
Block editor (Gutenberg)
Click the + where you want it, search for Custom HTML, and paste. Use Preview in the block toolbar to check it before publishing. The <!-- wp:html --> comments are optional - they only matter if you're pasting into the code editor rather than a block.
Classic editor
Switch from Visual to Text and paste there. Don't switch back to Visual before saving - the Visual tab has a habit of stripping iframes and scripts out of the markup.
Elementor, Divi, Beaver Builder
All three have an HTML or Code widget. Drag it in and paste. In Elementor the calculator sometimes won't render inside the editor canvas but is fine on the live page, so check the preview rather than trusting the builder.
Sidebar or footer widget area
Appearance → Widgets → Custom HTML. Sidebars are narrow, so drop the max-width from the snippet and let it fill the column. The calculator stacks its fields and gets taller when it's squeezed, which the resize script handles for you.
Tip Calculator
Tip math and bill splitting for any party size, with round-up and pre-tax options.
Get the code →Pregnancy Due Date
Estimated delivery date from LMP, conception, ultrasound, or reverse - with milestones.
Get the code →Blood Alcohol Estimator
BAC from drinks, weight, sex, and time, with time-to-sober projection.
Get the code →Concrete Volume
Cubic yards needed for slabs, columns, and post holes - plus bags, trucks, and cost.
Get the code →Take-Home Pay
Net paycheck after federal, state, FICA, and pre-tax deductions. 2026 brackets.
Get the code →MPG & Fuel Cost
Trip cost, true tank MPG, or two-vehicle annual comparison. Imperial & metric.
Get the code →