DATA
Mulch data downloads
Every table the calculators on this site use is published here as a plain CSV, so you can check the arithmetic, drop the numbers into a spreadsheet, or use them in your own project. Each file below states what it contains, the formula that produces it, and where any non-arithmetic figure came from.
Three groups of tables are published here: the coverage tables, the bag count tables, and the dated price and comparison tables.
Coverage tables
- mulch-coverage-by-depth.csv — square feet covered by one cubic yard at depths from one to six inches. Formula:
324 ÷ depth in inches. The 324 is 27 cubic feet per yard multiplied by 12 inches per foot. - rubber-bag-coverage-by-depth.csv — the same calculation for the bag sizes rubber mulch is actually sold in: 0.8, 1.25, 1.5 and 2 cubic feet, at depths from one to four inches. Formula:
bag cubic feet × 12 ÷ depth in inches. - bag-coverage-by-depth.csv — square feet covered by one bag at each depth for 1, 1.5, 2 and 3 cubic foot bags. Same formula, applied to the bag sizes bagged wood mulch is sold in.
Bag count tables
- mulch-bags-per-yard-table.csv — how many bags a given number of cubic yards becomes at each bag size, with the exact count, the whole bags to buy, and the leftover after rounding up.
- rubber-bags-for-common-bed-sizes.csv — whole bags needed for beds from 50 to 1,000 square feet at a 2-inch layer, for each rubber bag size.
Dated price and comparison tables
- mulch-yard-bulk-price-comparison-2026-09-17.csv — bulk mulch quotes collected on September 17, 2026, with the price basis, the price per cubic foot, and the page each figure came from.
- mulch-vs-pine-straw-comparison-2026-09-17.csv — wood mulch and pine straw normalised to cost per square foot at a 2-inch coverage, with the dated basis for each figure and its source page.
How to read the formula column
Coverage files carry a formula column that repeats the calculation in words for every row, so a value can be checked without trusting this site. If you spot a row that does not match its stated formula, that is a bug and we want to hear about it — see the contact page.
What is arithmetic and what is sourced
Two kinds of number appear in these files and they are not equally authoritative.
- Arithmetic. Cubic feet, cubic yards, coverage per yard and per bag, and bag counts are pure calculation from the definitions that one cubic yard is 27 cubic feet and one foot is 12 inches. Nothing here can go out of date.
- Dated observations. Prices and installed-cost ranges were collected on the date in the filename and column. They are a snapshot of what was published that day, not a live rate, and they change. Re-check before you buy.
- Cited figures. The weight range for a cubic yard of mulch (450–850 lb, from the University of Regina's Math Central) and the playground surfacing depths (CPSC Public Playground Safety Handbook, Publication 325) are not arithmetic. They are attributed on the pages that use them.
The same toolkit as code
The functions behind these tables are also published as a dependency-free JavaScript module with a test suite that checks every value in the CSVs against the formula that is supposed to produce it. That is at github.com/ERTHK/mulch-measure-calculator-kit under the MIT licence.
Cite this dataset
The mulch coverage, bag-count and dated price tables from this site are archived as a citable dataset: Mulch coverage, bag-count and dated bulk price tables, version v1, published 20 September 2026, 9 files, creator ERTHK — DOI 10.5281/zenodo.22855990, record at zenodo.org/records/22855990.
Released under CC0 1.0 Universal (Creative Commons Zero v1.0 Universal): free to copy, modify and redistribute.
The source library that generates the tables, with its test suite, is at github.com/ERTHK/mulch-measure-calculator-kit, released under the MIT license.
Two versions exist. The CSVs on this page are the rolling version kept up to date here. The archived dataset (10.5281/zenodo.22855990) is a version 1 snapshot taken on 20 September 2026. Where the two disagree, the dated figures published on this page are the current ones.
Related calculators
These files support the mulch calculator, the coverage calculator, the bag count guide, the rubber mulch calculator and the pine straw calculator. The yard price check explains how the dated price table is used.