🔷 菱形面积计算器Area of a Rhombus Calculator

使用说明与常见问题How-to & FAQ

「菱形面积计算器」是什么？What is the Area of a Rhombus Calculator tool?

按两条对角线、边长和高、或边长和内角三种方式计算菱形面积，同时给出边长、周长、两条对角线和内角。Find the area of a rhombus from its two diagonals, from side and height, or from side and an interior angle — with the side, perimeter, both diagonals and the interior angles.

如何使用「菱形面积计算器」？How do I use the Area of a Rhombus Calculator tool?

在「菱形面积计算器」中，填写「已知条件」、「对角线 p」、「对角线 q」、「边长 a」、「高 h」等参数，结果会随输入实时计算并显示在下方。In the Area of a Rhombus Calculator: Fill in "Known values", "Diagonal p", "Diagonal q", "Side a", "Height h"; results are recalculated instantly as you type.

菱形面积公式有哪些？What are the rhombus area formulas?

对角线 p、q：A = p × q ÷ 2；边长 a 和高 h：A = a × h；边长 a 和任一内角 θ：A = a² × sin θ。三种方法对同一个菱形结果相同。With diagonals p and q: A = p × q ÷ 2. With side a and height h: A = a × h. With side a and any interior angle θ: A = a² × sin θ. All three give the same area for the same rhombus.

边长和对角线有什么关系？How do the side and diagonals relate?

菱形的对角线互相垂直平分，所以边长 a = √((p/2)² + (q/2)²)；反过来，已知边长和内角 θ 时，两条对角线是 2a·sin(θ/2) 和 2a·cos(θ/2)。The diagonals bisect each other at right angles, so the side a = √((p/2)² + (q/2)²). Conversely, from side a and angle θ the diagonals are 2a·sin(θ/2) and 2a·cos(θ/2).

默认值是什么？What are the defaults?

默认的对角线 6 和 8（面积 24、边长 5）只是示例，请换成你的数值。The default diagonals 6 and 8 (area 24, side 5) are only an example — replace them with your own.

计算精度如何？How precise are the results?

「菱形面积计算器」使用 JavaScript 双精度浮点数（约 15–16 位有效数字）；极大或极小的数值可能存在精度误差。The Area of a Rhombus Calculator uses double-precision floating point (about 15–16 significant digits); very large or very small values may lose precision.

「菱形面积计算器」免费吗？需要注册吗？Is the Area of a Rhombus Calculator free? Do I need an account?

「菱形面积计算器」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Area of a Rhombus Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.