Square feet converter
43,560 square feet are exactly 1 acre, 4840 square yards and 4046.8564224 square metres. Enter an area in square feet once and get all three for a property listing, a floor plan or a landscaping estimate. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Square feet
- 43,560
- Square meters
- 4,046.8564224
- Acres
- 1
- Square yards
- 4,840
The square feet converter turns one area measurement into three widely used alternatives: square meters, acres, and square yards. Enter any non-negative finite number of square feet and receive all three converted values together, along with the original area for reference. The calculation uses fixed international definitions, including exactly 0.09290304 square meters per square foot, 43,560 square feet per acre, and 9 square feet per square yard. This makes the result useful for property listings, floor plans, landscaping estimates, and data normalization. The algorithm is deterministic and uses no network, clock, or randomness.
Understanding the three area conversions
Square feet are common in residential and commercial property descriptions, especially in the United States, while square meters are the standard area unit in most metric contexts. The relationship is fixed because the international foot is exactly 0.3048 meters, so one square foot is exactly 0.09290304 square meters. Acres describe larger parcels of land: one international acre contains exactly 43,560 square feet.
Square yards are often used for carpeting, paving, fabric, and landscaping, and one square yard contains exactly nine square feet. This converter applies all three relationships to the same input, which removes the need to submit separate calculations or copy values between tools. It multiplies square feet by 0.09290304 for square meters, divides by 43,560 for acres, and divides by 9 for square yards.
Because area units are squared, converting with a simple linear foot-to-meter value would be wrong. For example, multiplying an area by 0.3048 does not produce square meters; the linear factor must be squared. The exact area factor already does that work correctly.
Supplying input and reading the response
The value may be zero or positive, may include a decimal fraction, and must remain finite. Numeric strings are not accepted because the contract asks for a number explicitly; this prevents ambiguous values containing commas, unit labels, or locale-specific punctuation from being interpreted unexpectedly. Keeping every result in one flat object makes it straightforward to display the values in a form, save them as database columns, or use them in a spreadsheet export.
For an input of zero, every returned area is zero. Results are normalized to fifteen significant digits to suppress insignificant binary floating-point noise while preserving useful precision across small and large practical areas.
Checking results and choosing the right unit
A quick reasonableness check helps catch input mistakes before converted values enter a report. Square meters should be a little less than one tenth of the square-foot value, square yards should be exactly one ninth of it, and acres should be much smaller unless the input represents a large parcel. For example, a 9-square-foot area is exactly 1 square yard and about 0.83612736 square meters.
A 43,560-square-foot parcel is exactly 1 acre, about 4,046.8564224 square meters, and 4,840 square yards. Choose square meters for metric construction documents, international comparisons, and scientific datasets. Choose acres for lots, farms, parks, and other broad land areas.
Choose square yards for materials or projects commonly sold by that unit, but remember that a material order may require waste allowances that this pure area converter does not estimate. The capability does not convert lengths, calculate room area from dimensions, infer units from text, estimate price, or round to vendor package sizes.
What you can do with it
Property listing normalization
Convert a building area from square feet into metric square meters and land-friendly acres for international property records.
Flooring and landscaping estimates
Express a measured square-foot area in square yards before comparing products or contractor measurements quoted in that unit.
Dataset preparation
Add consistent square-meter, acre, and square-yard columns to records whose source area is stored in square feet.
FAQ
How do I convert square feet to square meters?
Multiply square feet by exactly 0.09290304. The converter applies this factor automatically.
How many square feet are in an acre?
One international acre contains exactly 43,560 square feet, so acres equal square feet divided by 43,560.
How do I convert square feet to square yards?
Divide square feet by 9 because one square yard contains exactly nine square feet.
Why can't I just multiply square feet by 0.3048?
Because 0.3048 is the factor for length, not area. A square foot is a square, so the length factor must be squared, which gives exactly 0.09290304 square metres per square foot.
How can I tell if a converted area makes sense?
Square metres should be a little less than one tenth of the square-foot figure, square yards exactly one ninth of it, and acres much smaller unless you entered a large parcel of land.
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/conv/square-feet-converter \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"square_feet":1000}'const res = await fetch("https://api.kit.forhosting.com/conv/square-feet-converter", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"square_feet": 1000
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/square-feet-converter",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"square_feet": 1000
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/square-feet-converter", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"square_feet":1000}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"square_feet":1000}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/square-feet-converter", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"square_feet": 1000
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.square_feet_converter",
"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
Missing, negative, infinite, or non-numeric input returns a clear invalid_input error rather than an invented result.
Supplying input and reading the response
Send an object containing the required square_feet field as a JSON number. A successful response echoes square_feet and returns square_meters, acres, and square_yards as numeric fields.
Checking results and choosing the right unit
It only translates an already-known non-negative area in square feet, ensuring that repeated API and browser calculations produce the same deterministic numeric structure.
Technical questions
Can the input be zero or a decimal?
Yes. Zero and non-negative finite decimal numbers are valid; negative values and non-finite values return invalid_input.
What does the square feet converter cost?
The browser calculation is free. A successful API request costs $0.002; invalid requests return an error.