🧊 正方体计算器Cube Calculator
已知正方体的棱长、体积、表面积、面对角线或体对角线中的任意一个，求出其余所有量。Give any one of a cube's edge, volume, surface area, face diagonal or space diagonal and get the rest.
使用说明与常见问题How-to & FAQ
「正方体计算器」是什么？What is the Cube Calculator tool?
已知正方体的棱长、体积、表面积、面对角线或体对角线中的任意一个，求出其余所有量。Give any one of a cube's edge, volume, surface area, face diagonal or space diagonal and get the rest.
如何使用「正方体计算器」？How do I use the Cube Calculator tool?
在「正方体计算器」中，填写「已知量」、「数值」等参数，结果会随输入实时计算并显示在下方。In the Cube Calculator: Fill in "Known value", "Value"; results are recalculated instantly as you type.
正方体公式？Cube formulas?
棱长 a：体积 a³，表面积 6a²，面对角线 a√2，体对角线 a√3。With edge a: volume a³, surface area 6a², face diagonal a√2, space diagonal a√3.
由体积怎么求棱长？Edge from volume?
棱长等于体积的立方根，例如体积 64 时棱长为 4。The edge is the cube root of the volume — volume 64 gives edge 4.
计算精度如何？How precise are the results?
「正方体计算器」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 Cube Calculator uses double-precision floating point (about 15–16 significant digits); very large or very small values may lose precision.
「正方体计算器」免费吗？需要注册吗？Is the Cube Calculator free? Do I need an account?
「正方体计算器」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 Cube 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.