What Is the Lawn Area Calculator?
This tool estimates the total surface area of your lawn or yard so you can buy the right amount of grass seed, sod, fertilizer, or weed control. Because most yards aren't a single neat rectangle, the calculator lets you break your lawn into up to three rectangular sections and adds them together. The result is shown in square feet, square yards, square meters, and acres.
How to Use It
Walk your yard and measure each rectangular patch of grass with a tape measure or measuring wheel. For irregular shapes, divide the lawn into the closest rectangles you can — driveways, flower beds, and the house footprint should be left out. Enter the length and width of each section in feet. Leave unused sections at zero. The calculator multiplies length by width for each piece and sums them.
The Formula Explained
The area of a rectangle is length times width. The total lawn area is simply the sum of all sections:
To convert square feet to square yards, divide by 9 (since 1 yard = 3 feet, 1 yd^2 = 9 ft^2). To convert to acres, divide by 43,560 ft^2. For square meters, multiply by 0.09290304.
Worked Example
Suppose the front yard is 40 ft × 25 ft and the back yard is 50 ft × 30 ft. Front = 1,000 ft², back = 1,500 ft², total = 2,500 ft². That's about 277.78 yd², roughly 232.26 m², or 0.0574 acres.
使用注意事項與精準校對原則（6 大核心守則）
📐 1. 嚴格對齊輸入量綱與單位
輸入各項數值時請務必確認量綱（例如小時、天數、金額、百分比），避免單位不匹配引發推算偏差。
🔒 2. 純前端本機毫秒級隱私保障
所有計算邏輯 100% 在您的終端瀏覽器內完成，資料絕不上傳伺服器，嚴格守護商業與個人隱私。
📊 3. 符合公認學術與產業計算模型
演算法嚴格遵循國際通用數學公式與標準計算模型，經多重情境交叉核對，數值嚴密精確。
📋 4. 一鍵複製與免登入 PDF 匯出
支援一鍵複製推算結果字串至剪貼簿，亦可直接點擊列印按鈕輸出純淨 PDF 工作報表。
🔄 5. 多情景敏感度動態對比
建議針對極端值與多組預期情景分別試算，觀察輸出數據的波動區間，輔助做出更穩健的決策。
🛡️ 6. 專業諮詢與日常參考免責聲明
本工具運算結果供日常排程、學業研習與事前參考之用，如涉及重大法規或投資決策請諮詢持證專家。