Mulch calculator
A 200 square foot bed mulched 3 inches deep takes 50 cubic feet, or 1.8519 cubic yards for a bulk order, which is 25 bags of the common 2 cubic foot size. Enter bed area and depth to compare bulk and bagged mulch. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Area
- 200
- Depth
- 3
- Area sqft
- 200
- Depth inches
- 3
- Bag size cu ft
- 2
- Volume cu ft
- 50
This mulch calculator turns garden bed area and a target mulch depth into the cubic yards of mulch you should order and the number of retail bags that cover the same volume. Landscapers, homeowners, and HOA crews routinely under-order when they forget that depth is measured in inches while bulk mulch is sold by the cubic yard, or they over-buy bags because the cubic-foot bag label never matches a mental yardage guess. The engine accepts area in square feet, depth in inches, and an optional bag size in cubic feet (default two cubic feet, the common bag at big-box stores). Volume in cubic feet is area times depth over twelve; cubic yards divide that result by twenty-seven, which is the same identity as area times depth over three hundred twenty-four. Bag count ceilings the cubic-foot need by bag size so you never leave a partial bag on the math. The response is fully deterministic with no network calls, no sampling, and no date-dependent shortcuts.
What the calculator returns and how mulch volume is defined
Mulch volume here is the bulk material needed to cover a flat bed area to a uniform depth, expressed both in cubic feet and in cubic yards, plus a whole-bag count for bagged product. Cubic yards are the unit bulk suppliers use for dump-truck or super-sack orders; cubic feet are the unit printed on retail bags.
The conversion is exact in the identity used by every landscape sheet: one cubic yard equals twenty-seven cubic feet, and depth in inches must be divided by twelve before multiplying by area in square feet. Equivalently, cubic yards equal area times depth in inches divided by three hundred twenty-four, because twelve times twenty-seven is three hundred twenty-four. The calculator multiplies area by depth over twelve for cubic feet, divides by twenty-seven for cubic yards, and ceilings cubic feet over bag size for bags.
Treat the result as a planning estimate and round up slightly for irregular beds, settling, or pathways that will also receive mulch.
Where mulch estimates fit for DIY, quotes, and software
DIY gardeners meet this problem when a spring bed refresh needs two to three inches of hardwood mulch, when a new shrub border is measured in feet but the bag aisle is labelled in cubic feet, or when a bulk yard order must be compared against bagging the same volume at the store.
Trade estimators use the same identity across dozens of beds: measure plan area, pick a depth from the plant list, convert to yards for the delivery truck, and optionally convert to bags for small jobs where bulk does not make sense. Teachers and vocational trainers can pre-generate answer keys for modest bed sizes without trusting opaque mobile apps that switch units mid-form or forget that depth is inches while area is square feet.
Developers call the same contract from scripts to seed deterministic test vectors for landscape calculators, to normalise user-entered bed sizes before a cart suggests bag counts, or to satisfy programming-challenge statements that demand cubic yards rather than a hand-waved “about two yards.” Product tools use the rewrite when a homeowner types two hundred square feet and three inches and the UI must show yardage and a clean bag total before checkout.
What you can do with it
Weekend garden bed refresh
Enter bed area in square feet and a two-to-three inch depth to know cubic yards for bulk delivery or bags for a store run.
Contractor multi-bed quotes
Feed measured bed areas and specified depths from a plant schedule to produce reproducible yardage and bag totals for bids.
FAQ
What does the mulch calculator cost?
It is free in your browser on this page.
What bag size does the calculator assume?
The default is 2 cubic feet per bag, a common retail size.
Does this account for slope or compaction?
No. It assumes a flat area and uniform depth. Add a small contingency yourself for slopes, settling, or irregular bed shapes.
How deep should I spread mulch?
Typical garden beds use 2 to 4 inches, and a spring refresh of hardwood mulch is often 2 to 3 inches. Enter the depth in inches; the calculator divides it by 12 before multiplying by the bed area.
Should I order bulk mulch or bags?
Bulk suppliers sell by the cubic yard for truck or super-sack deliveries, while store bags are labelled in cubic feet. The result gives both figures for the same volume, so you can compare a delivery with bagging the job.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/home/mulch \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"area":200,"depth":3}'const res = await fetch("https://api.kit.forhosting.com/home/mulch", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"area": 200,
"depth": 3
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/home/mulch",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"area": 200,
"depth": 3
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/home/mulch", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"area":200,"depth":3}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"area":200,"depth":3}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/home/mulch", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"area": 200,
"depth": 3
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "home.mulch",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Limits
max_abs | 1000000000 |
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
What the calculator returns and how mulch volume is defined
The JSON response echoes area_sqft, depth_inches, bag_size_cu_ft, volume_cu_ft, volume_cu_yd, bags as a whole number, unit tags, the method tag, and a short formula string. There is no brand database, no slope correction, no compaction factor, and no shopping cart: the page answers only the volume and bag questions with stable numbers suitable for worksheets, contractor quotes, and API consumers that must match goldens run after run.
How inputs are read, validated, and kept reproducible
Preferred fields are area for bed surface in square feet and depth for mulch thickness in inches, plus optional bag_size in cubic feet when you are not using the default two-cubic-foot bag. Aliases such as bed_area, sqft, and square_feet for area, depth_inches, inches, and mulch_depth for depth, and bag_cu_ft or bag_volume for bag size are accepted so spreadsheets, query strings, and typed forms can reuse the same contract without renaming columns. Every numeric field must be finite; non-positive area, depth, or bag_size is rejected with invalid_input so a zero-depth form field cannot silently claim free mulch. An optional precision field, with aliases decimals and dp, chooses how many decimal places to expose for areas and volumes, defaulting to four and capped at fifteen so JSON goldens stay stable across engines. Pair the free browser run on this page with the priced API when you need the identical mathematical result inside an automated pipeline without re-implementing the mulch formula yourself.
Where mulch estimates fit for DIY, quotes, and software
On this page the work runs entirely in your browser; through the API each successful lookup costs $0.002, failed validation is not charged, and nothing is stored after the response returns. That split — free interactive exploration and a priced, identical API — matches the rest of the KIT tier-A catalog and lets you move from a backyard demo to an automated quoting pipeline without changing the mathematical result. Pair it with unit converters when your tape measure is in metres, and with other home or geometry endpoints when you are building a small lab of free, deterministic planning helpers for outdoor projects.
Integration use cases
Deterministic fixtures for apps
Generate stable volume_cu_yd and bags values for unit tests in landscape planners, e-commerce bag suggesters, and CI checks.
Technical questions
How is mulch volume calculated?
volume_cu_ft = area_sqft × (depth_inches / 12); volume_cu_yd = volume_cu_ft / 27 (same as area × depth / 324). bags = ceil(volume_cu_ft / bag_size).
What if I enter zero or negative area or depth?
The request fails with invalid_input. Area, depth, and bag_size must all be strictly positive numbers greater than zero.