Soil calculator
A bed 8 by 4 feet filled 1 foot deep holds 32 cubic feet of soil, a little more than one cubic yard: the calculator gives the volume in cubic feet, cubic yards, cubic metres and litres before you order. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Length
- 8
- Width
- 4
- Depth
- 1
- Area
- 32 ft
- Volume
- 32
- Volume ft3
- 32
- Volume yd3
- 1.1851851852
Filling a raised garden bed is a shopping problem before it is a planting problem: a box of known interior length, width, and fill depth holds a fixed rectangular volume of soil mix, and ordering too little means a second delivery while ordering too much leaves opened bags to store. This soil calculator multiplies those three dimensions after converting them into one consistent length unit, then reports the fill volume in the input unit cubed and in the four units bulk and bagged garden soil are actually sold in: cubic feet, cubic yards, cubic metres, and litres. Defaults match a typical North American bed measured in feet; switch unit to inches, metres, or centimetres when the tape and the supplier disagree.
How raised-bed soil volume is computed from length, width, and depth
A raised bed is a rectangular prism whose interior is filled with soil, so the volume of mix you need is the product of interior length, interior width, and the depth you intend to fill, not the outside frame size and not a guessed bag count. Write volume in the input unit cubed as length times width times depth, then convert the same three numbers into feet and into metres so cubic yards and litres follow from fixed constants rather than a second hand calculation.
Cubic feet is the product of the three dimensions expressed in international feet; cubic yards is that cubic-foot figure divided by twenty-seven, the exact number of cubic feet in a cubic yard; cubic metres is the product of the three dimensions expressed in metres; litres is cubic metres times one thousand. When you omit the optional unit field the calculator assumes feet, which matches a common four-by-eight bed one foot deep: eight times four times one is thirty-two cubic feet, a little more than one cubic yard.
Explicit unit values are feet, inches, metres, or centimetres, and all three axes share that unit so you cannot accidentally mix a metric length with an imperial depth. Conversion uses the exact international foot of zero point three zero four eight metres, zero point zero two five four metres per inch, and one centimetre as one hundredth of a metre. The pipeline is deterministic floating-point arithmetic with no random seeds, no wall-clock timestamps, and no network calls.
Negative length, width, or depth is rejected because a negative edge does not describe a physical box; a value that is not a finite number is rejected for the same reason.
What you send, what you get back, and how errors are reported
Send three required finite numbers: length for the interior long side of the bed, width for the interior short side, and depth for the soil height you will actually fill, which may be less than the board height if you leave headroom for mulch. Optionally send unit as ft, in, m, or cm; omitted unit defaults to feet. Zero is allowed and returns a zero volume, which is the honest result when a bed is not being filled.
A classic check is an eight-by-four-by-one foot bed: thirty-two cubic feet, thirty-two twenty-sevenths of a cubic yard, and the matching cubic metres and litres from the international-foot path. Wire the free browser form for a single weekend bed, then call the identical contract from scripts when you need a row of identical boxes.
Where a raised-bed soil calculator shows up in real work
Home gardeners building a first four-by-eight vegetable box need a trustworthy cubic-yard or litre figure before buying bagged garden soil or calling a bulk supplier, especially when bags are sold in one-and-a-half cubic foot sacks and bulk trucks have a minimum load. Community gardens and school plots often install several identical frames in one weekend; feeding each length-width-depth triple through the same formula keeps the purchase order aligned with the lumber cut list instead of a round-number guess copied from a forum.
Nurseries and garden centres can sit this helper next to bulk soil and raised-bed kits so a shopper who knows the inside of the box in feet or centimetres leaves with a volume in the unit the product is sold in. Landscape crews quoting fill for rooftop planters and courtyard troughs that happen to be rectangular use the cubic-metre result on metric drawings and the cubic-yard result on US material tickets without maintaining two spreadsheets.
If you later need bag counts from a specific bag yield, a waste percent, circular beds, or a compost-topsoil-peat mix recipe, treat those as separate search intents rather than overloading this length-width-depth soil volume page.
What you can do with it
Weekend 4×8 vegetable bed fill
Enter interior length, width, and fill depth of a new raised bed and order cubic yards or litres of mix without a second trip or leftover bags.
Nursery and garden-centre quoting
Convert a customer's box dimensions into the unit bulk soil and bagged garden mix are sold in, using the same numbers the tape measure showed.
School and community garden take-off
Run each identical or unique frame through length × width × depth so one purchase order covers every bed in the plot.
FAQ
How do I calculate how much soil a raised bed needs?
Send finite length, width, and depth in the same unit (default feet).
What happens if length, width, or depth is negative?
A negative edge does not describe a physical raised bed, so the calculator will not return a negative soil volume.
Which unit should I use for the bed dimensions?
Use one shared unit for all three axes: ft (default), in, m, or cm. Do not mix systems. The response still includes cubic feet, cubic yards, cubic metres, and litres.
What does the soil calculator cost?
The browser tool is free and runs locally.
How many cubic yards of soil fill a 4 by 8 bed one foot deep?
A little more than one cubic yard. Eight times four times one gives 32 cubic feet, and dividing by twenty-seven, the number of cubic feet in a cubic yard, puts the order just above one yard.
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/bio/soil \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"length":8,"width":4,"depth":1}'const res = await fetch("https://api.kit.forhosting.com/bio/soil", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"length": 8,
"width": 4,
"depth": 1
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/bio/soil",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"length": 8,
"width": 4,
"depth": 1
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/bio/soil", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"length":8,"width":4,"depth":1}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"length":8,"width":4,"depth":1}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/bio/soil", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"length": 8,
"width": 4,
"depth": 1
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "bio.soil",
"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.
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
Length, width, and depth must be finite numbers; a negative dimension is rejected with invalid_input instead of a silent negative volume. The same pure arithmetic powers the free browser tool and the API at $0.002 per successful call, with no network, no random compaction factor, and no date-dependent rounding, so a weekend plan and a later script stay aligned.
What you send, what you get back, and how errors are reported
Each required field may arrive as a JSON number or as a numeric string; missing fields, empty strings, NaN, and Infinity fail with invalid_input naming the field, and those failures are not billed. If length, width, or depth is negative the request fails with a message that the dimension cannot be negative, so a sign error from a spreadsheet export is caught before it becomes a nonsense order. On success the body echoes cleaned inputs and the resolved unit, plan area as length times width, volume in the input unit cubed as the primary fill figure, volume_ft3, volume_yd3, volume_m3, volume_l, a formula string restating the prism identity, and a short message that repeats the four purchase units. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance.
Where a raised-bed soil calculator shows up in real work
Because this capability is a pure parse engine, API pricing is the published base of $0.002 per successful item and failed validation does not consume balance.
Technical questions
Does this include extra soil for settling or bags?
No. It returns geometric fill volume only. Divide volume_ft3 or volume_l by the bag yield printed on the product, and add your own waste factor if the mix will settle.