CalcHive

CalcHive › Embed

Free calculators for your website

Last updated: October 6, 2026

Put a CalcHive calculator on your own page with an iframe. The widgets are free.

A landscape or fence page can offer a sod, concrete, or lumber check next to a quote form. A paint counter can let someone estimate gallons before they call. A recipe post can resize a cake pan beside the ingredient list. Each widget is the form and the result from an existing CalcHive tool, plus a small line that reads Calculator by CalcHive and links to the full page.

There is no mulch calculator on this site. The other DIY tools are board feet and a fuel-economy comparison. Board feet is the material takeoff, so that is the widget in the mulch slot. It answers a lumber order. It does not answer cubic yards of mulch. Concrete volume is already its own widget, for a slab, a footing, or a round column.

How to add one

  1. Pick a calculator below and press Copy iframe code.
  2. Paste the snippet into the HTML of your page, where the calculator should appear. A custom HTML block is the usual place in a site builder that otherwise strips iframes.
  3. The width is 100 percent, so the frame follows the column you put it in, up to 520 pixels. The height is enough for the form and the result at that width.
  4. Publish, then run one example on your page and on the full CalcHive tool. The numbers should match.

In a column narrower than about 420 pixels, the fields stack and the frame may scroll. The CalcHive line stays along the bottom of the frame while it scrolls. If you shorten the height, keep that line on screen.

The credit line

Every widget ends with the words Calculator by CalcHive. That text is a link to the full tool on calchive.org, and it opens in a new tab. The link is the credit for using the widget. Leave it visible. Do not crop the iframe so the line is cut off, and do not cover it with another element. The anchor text is the name CalcHive.

The widget is the form only. The full tool page has the worked examples, the unit notes, and the limits. Send people there when they need the longer explanation.

What the frame does not include

The widget pages are not a second copy of the article, and they are not meant to be indexed. Each one points search engines at the full tool page. They also do not load ads. What you see in the frame is the calculator and the credit line.

Jump to a widget: Sod, Concrete, Paint, Board feet, Pan size.

Sod calculator

Rectangle, square, circle, or a square-footage total you already measured. Dimensions are in feet. The tool adds 5 percent and rounds up to whole pallets. Square feet per pallet starts at 450. Replace that with the number on the supplier's quote. Price per pallet is optional. The full page is the sod calculator.

A 40 foot by 30 foot rectangle at 450 square feet per pallet, at $200 a pallet, is 3 pallets and $600. That $600 is pallets times price. Delivery is not included.

Concrete volume calculator

A slab uses length and width in feet and thickness in inches. A footing uses length in feet, and width and depth in inches. A round column uses diameter in inches and height in feet. The count multiplies identical pours. The headline is exact cubic yards. A separate line is that yardage times 1.10. Bag counts use the exact cubic feet, not the cushion: 0.45 cubic feet for a 60 lb bag and 0.60 for an 80 lb bag, rounded up. Read the yield on the bag you buy. The full page is the concrete volume calculator.

A slab 20 feet by 10 feet at 4 inches is 2.47 cubic yards, 2.72 cubic yards with the 10 percent line, 149 of the 60 lb bags, and 112 of the 80 lb bags. The bag counts do not include the 10 percent.

Paint coverage calculator

Wall area is the perimeter times ceiling height, not the floor. Each door counts as 21 square feet and each window as 15 square feet. Those are the allowances built into the form. Coverage needed is the paintable area times the number of coats, then divided by square feet per gallon. The buy line rounds up to a whole gallon. The fields start at a 9 foot ceiling, 2 doors, 2 windows, 2 coats, and 350 square feet per gallon. Change the coverage number to the one on the can. The full page is the paint coverage calculator.

A 12 by 14 foot room with a 9 foot ceiling, 2 doors, 2 windows, 2 coats, and 350 square feet per gallon is 2.26 gallons, so 3 gallons to buy.

Board feet calculator

This is the stand-in for a mulch widget, because CalcHive does not have a mulch calculator. Board feet are for a lumber order: thickness in inches, width in inches, length in feet, and a piece count. One piece is thickness times width times length, divided by 12. The page does not add a waste percent, and it does not turn a nominal 2 by 4 into 1.5 by 3.5. You type the inches the seller is charging for. Price per board foot is optional. A blank price shows N/A. The full page is the board feet calculator.

A board 1 inch by 6 inches by 8 feet, one piece, at $6 per board foot, is 4 board feet and $24.

Baking pan size converter

The tool lives at /tools/cooking/pan-size-converter/. It compares the floor area of the pan in the recipe with the pan you have, and prints the factor to multiply every ingredient by. A round pan uses the diameter, the distance across, not the radius. A square uses the side. A rectangle uses length and width. The factor is new area divided by original area. It keeps a similar depth of batter. It does not change the oven temperature or the bake time. The chart that uses this same area math is the baking pan conversion chart.

A 9 inch square into a 10 inch round is a factor of 0.97. The square is 81 square inches. The round is about 78.54 square inches.

Questions

Are the widgets free?

Yes. Copy an iframe from this page and paste it into your own page. There is no account and no fee.

Will a widget match the full calculator?

Yes. The widget and the full tool page load the same calculation script. Enter the same numbers in both and the result is the same.

Do I have to keep the CalcHive link?

Yes. Every widget ends with the words Calculator by CalcHive. That line is a link to the full tool, and it opens in a new tab. Leave it visible. Do not crop the iframe so the line is cut off, and do not cover it.

Is there a mulch calculator?

No. CalcHive does not have a mulch calculator. The closest existing DIY tool is the board feet calculator, and that is the widget in this set. It totals a lumber order from thickness, width, length, and a piece count. It does not estimate cubic yards of mulch.

Do the widgets show ads?

No. A widget is the form, the result, and the CalcHive link. The widget pages do not load ads.

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