Playground Mulch Calculator

Enter the play area and the surfacing — wood chips, wood mulch, rubber, pea gravel or sand — and get the cubic yards to install at CPSC's minimum depth, allowing for compression.

Workplace & SafetyUnited States onlySource: U.S. CPSC Public Playground Safety Handbook, Table 2 and §2.4.2.2Free, no sign-up

Length (ft)

Width (ft)

Surfacing material

Highest fall height, ft (optional check)

Bag size, cu ft (optional)

These are the equipment’s own dimensions — add CPSC’s general 6 ft use zone on every side

The answer updates as you type; nothing is sent anywhere.

Wood chips over 20 × 30 ft (600 sq ft)

22.22 cubic yards

600 cu ft (16.99 m³) at an initial fill of 12 in, so it settles to the 9 in minimum after compressing 25%.

The arithmetic

Minimum compressed depth 9 in (Table 2) ÷ 0.75 = 12 in initial fill. 600 sq ft × 12 ÷ 12 = 600 cu ft ÷ 27 = 22.22 cu yd.

What this page cannot tell you

This is a quantity based on CPSC’s minimum depths, not a safety assessment. Use zones differ by equipment — swings and slides need more than 6 ft — and engineered wood fiber or rubber products should come with the maker’s ASTM F1292 test data and depths. Loose fill needs regular topping up to stay at depth.

How to work out playground mulch

Measure the surfaced area. Enter the length and width in feet of the area to cover. If you only have the equipment's own size, tick the box to add CPSC's general 6-foot use zone on every side.
Pick the material. CPSC Table 2 lists wood chips, wood mulch (non-CCA), shredded/recycled rubber, pea gravel and sand, each with a minimum compressed depth.
Check the fall height. Enter the highest fall height to see whether Table 2 lists that material as protecting to it.
Read the quantity. Loose fill compresses at least 25%, so a 9-inch minimum means a 12-inch initial fill. The result is the volume at that initial depth, in cubic yards and bags.

10 situations where a playground mulch calculation helps

Ordering mulch for a school playground

A facilities manager can turn the playground's footprint into cubic yards at the depth CPSC lists.

Planning a backyard play set

Parents adding a swing set can see how much loose fill the area needs, including the use zone around it.

Choosing between wood chips and mulch

In Table 2, 9 inches of wood chips protects to 10 ft and 9 inches of wood mulch to 7 ft, so the material matters for taller equipment.

Pricing rubber mulch

Rubber's minimum is 6 inches and CPSC notes it does not compress like other loose fill, so it needs half the volume of a 12-inch wood fill.

Allowing for settling

The tool applies CPSC's 25% compression so the order is for the initial fill, not the compressed depth.

Checking a tall structure

Entering the fall height flags materials Table 2 does not list as reaching it.

Church and daycare play areas

Small organisations can estimate bulk deliveries or bag counts before buying.

Converting to bags

Entering the bag size in cubic feet gives the number of bags, rounded up.

Budgeting a refurbishment

Running the area with each material shows the volume difference between options.

Explaining depth to a committee

The result cites the handbook's own table and example, which is easy to share.

Where the depths come from

The depths are from the U.S. Consumer Product Safety Commission's Public Playground Safety Handbook (Publication 325). Its Table 2, 'Minimum compressed loose-fill surfacing depths', lists 6 inches of shredded/recycled rubber as protecting to a 10 ft fall height, and 9 inches of sand (4 ft), pea gravel (5 ft), wood mulch, non-CCA (7 ft) and wood chips (10 ft). The handbook says the depths assume the material has been compressed by use and weathering.

Section 2.4.2.2 says loose-fill materials 'will compress at least 25% over time', with the example that if a playground will require 9 inches of wood chips, the initial fill level should be 12 inches. The calculator applies that: initial depth = minimum ÷ 0.75. For rubber, Table 2's footnote says it does not compress in the same manner, so its 6 inches is used as is. The same section says never to use less than 9 inches of loose fill except shredded/recycled rubber (6 inches recommended).

For the optional use zone, §5.3.10 says that where not specified elsewhere the use zone should extend a minimum of 6 feet in all directions from the perimeter of the equipment. Swings, slides and some other equipment have longer use zones in their own sections. Volume = area × initial depth; cubic yards = cubic feet ÷ 27. Nothing is fetched while you use the page.

The limits: this calculates a quantity at the handbook's minimum depths. It does not assess a playground's safety, account for equipment-specific use zones, or replace an engineered wood fiber or rubber product's own ASTM F1292 test data, which the handbook says manufacturers should provide.

Sources

U.S. CPSC — Public Playground Safety Handbook (Pub. 325, PDF) — Table 2 minimum compressed loose-fill depths; §2.4.2.2 compression; §5.3.10 use zone

Frequently asked questions

How deep should playground mulch be?

CPSC's Table 2 lists a minimum compressed depth of 9 inches for wood mulch, wood chips, sand and pea gravel, and 6 inches for shredded/recycled rubber. Because loose fill compresses at least 25%, the handbook's example installs 12 inches to keep 9.

How many cubic yards of mulch do I need for a playground?

Multiply the area in square feet by the initial depth in feet and divide by 27. A 20 × 30 ft area at 12 inches is 600 cu ft, or 22.2 cubic yards.

What fall height does wood mulch protect?

9 inches of wood mulch (non-CCA) is listed as protecting to a 7 ft fall height; 9 inches of wood chips to 10 ft.

How much rubber mulch do I need?

CPSC lists 6 inches of shredded/recycled rubber as protecting to 10 ft, and notes it does not compress like other loose fill. A 20 × 30 ft area at 6 inches is 300 cu ft, about 11.1 cubic yards.

How far around the equipment should the mulch go?

For equipment not covered elsewhere, the handbook says the use zone should extend at least 6 feet in all directions. Swings and slides have their own, longer use zones in the handbook.

Can I use pea gravel or sand?

They are in Table 2, but 9 inches protects to lower fall heights: 5 ft for pea gravel and 4 ft for sand.