Almost no garden is one rectangle. Measure it in pieces, add the parts that count and subtract the parts that do not, then carry the total into whichever material calculator you need.
A 10 m × 5 m back lawn plus a 4 m × 3 m side strip.
62.00 square metres (m²)
| Material assumptions | none — this tool measures only |
|---|---|
| Units used | m |
This is an example, not your result. It matches golden vector G2 in the calculation methodology. Enter your own measurements and select Calculate.
Almost no garden is one shape. The reliable method is to break it into pieces you can measure with a tape and a straight line: rectangles for the bulk of it, a circle for a round bed, a triangle for the corner where the fence cuts across, and a directly entered figure for anything you already know. Add the pieces that count and subtract the ones that do not.
Two rectangles of 10 m × 5 m and 4 m × 3 m come to 62.00 m². Subtract a round bed of 1 m radius from the first and the total drops by 3.14 m². Every row shows its own area as you type, so a mistyped dimension is obvious before you calculate anything.
Each dimension carries its own unit, so a tape marked in feet and a plan drawn in metres can go into the same worksheet. Feet convert at exactly 0.3048 m. Decimal commas work as well as decimal points — 2,5 and 2.5 are the same number here — and a value with both is rejected rather than guessed at, because guessing wrong turns 1,234.5 into a tenfold error.
Once you have a total, the result card offers a link into each material calculator carrying the area with it. The receiving page validates it exactly as it would validate something you typed, fills in a single measured-area row labelled as coming from your worksheet, and leaves the result waiting for you to press Calculate. If the value is malformed or out of range it is ignored silently and the page loads as a normal first visit.
Area is transparent arithmetic and needs no authority, which is why this page cites nothing. It is still only as good as the tape work: a sloping lawn has more surface than its plan area, a hand-measured curve is an approximation, and a garden measured on a windy day with a fabric tape is an estimate too. Round up rather than down when you are unsure, and note which rows you were confident about.
Every step is arithmetic you can repeat by hand. Full precision is kept through the calculation and rounded once for display.
| Step | Formula |
|---|---|
| Feet to metres | 1 ft = 0.3048 m |
| Rectangle area | A = length × width |
| Circle area | A = π × r², with r = d ÷ 2 when a diameter is entered |
| Triangle area | A = base × perpendicular height ÷ 2 |
| Measured area | A = the area you entered, in m² |
| Net area | net area = sum of added areas − sum of subtracted areas |
The calculation methodology sets out every formula, bound and rounding rule this site uses.
This page cites nothing, because everything on it is arithmetic you can check by hand. The formulae are set out in the calculation methodology.