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Free Fence Calculator

Calculate posts, rails and panels or pickets needed for a fence run.

What is the Fence Calculator?

Calculate posts, rails and panels or pickets needed for a fence run.

The fence length minus gate widths is divided by post spacing and rounded up to give sections. Posts are sections plus one, plus one extra per gate, rails are sections times rails per section, and pickets are run length divided by picket width plus gap, with waste.

Home and building jobs are easier to price when you know how much material you really need. A quick estimate also helps you avoid buying too little or too much.

How to use the Fence Calculator

Using the fence calculator takes a minute or two. Your entries are saved in this browser, so you can come back later and carry on.

Step 1

Enter the measurements of the area you are working on.

Step 2

Read the amount of material needed, including a waste allowance where relevant.

Step 3

Round up when you buy, and check the figures with your supplier.

Tips for better results

Corner and end posts may need closer spacing or larger sizes, so adjust spacing to suit your layout. Check local rules on fence height, setbacks and property lines before building.

Add 5 to 10 percent for waste, cuts and mistakes.

Measure twice, order once, and check quantities with your supplier.

Privacy and where your data goes

Everything you type into the fence calculator stays on your own device. Zapxa does not receive your numbers or documents. If you clear your browser data, your saved entries will be removed, so download a PDF of anything you want to keep.

Frequently asked questions

How many posts do I need for 100 feet of fence?

With 8 ft spacing and one 4 ft gate, the run is 96 ft, giving 12 sections, 13 posts and one extra gate post, for 14 in total.

Does picket spacing change the count?

Yes. Each picket takes its width plus the gap, so wider gaps reduce the number of pickets needed along the run.

Is the fence calculator free?

Yes. It is free to use with no signup, no watermark and no usage limits.

Is my data private?

Yes. Your inputs are processed in your browser and saved only in its local storage. They are not uploaded to our servers.

Does it work on mobile?

Yes. Zapxa works on phones, tablets and desktops. Use the print button or download a PDF to keep a copy.

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