Deck Load Calculator

Calculate deck attached to the house.

This app calculates the design load over each pier. It does not calculate the beam size. Larger post spacing will require larger beams. For beam sizes, use our Beam Calculator or contact an Engineer with your project details.

This app is designed with the Ledger Deck Foot Anchor (5" blade) because it has been loaded in clay soil up to 5,550#. You may use this app for any other footing provided you understand the footing and the soil bearing capacity of your site.

If using the Ledger Deck Foot anchor we recommend you design the deck to load no more than 4,000# on a pier. This is also a reasonable value for most other footings.

The Number of Piers in the report is for each beam.

We do not guarantee the accuracy of this program and use of this program is at your own risk. For certainty we recommend you contact a local engineer to verify pier loading for your project.



Enter the number of piers per beam:

Enter length of deck parallel to house: ft

Enter width of deck perpendicular to house: ft

Enter distance of beam from house: ft

Enter cantilever of beam beyond last pier (0 or greater): in

Dead Load: PSF

Ground Snow Load: PSF

Live Load: PSF

This app is designed with the Floating Deck Foot Anchor and operates differently than our calculator for Deck Attached to House.

This calculator determines the size of each tributary area of your deck. It then determines the total load from each tributary area based on the design load of your deck. Default is 50 psf which you can change.

The total load for each tributary area is then divided by the area of each footing in order to determine the load psf imposed on the soil.

This value must not be greater than the bearing capacity of the soil. If it is, you must increase the size of the footing to spread the weight out over a greater surface area or increase the number of footings.

For help, simply click on the(?) beside the section you need help with, Or watch this Tutorial Video.


Freestanding Deck

Soil Bearing Capacity: PSF

Number of Supporting Beams: (not including ledger)
Number of Support Posts Per Beam:

Design Load (suggested 50lbs/sqft):

Footing Type: Round | Rectangular