Number.MIN_VALUE

¥Value

2^-1074，或 5E-324。

¥2^-1074, or 5E-324.

¥Description

Number.MIN_VALUE 是可以在浮点精度内表示的最小正数（不是最大负数），换句话说，是最接近 0 的数字。ECMAScript 规范没有定义实现需要支持的精确值 - 相反，规范说，"必须是实现实际可以表示的最小非零正值"。这是因为小的 IEEE-754 浮点数是 denormalized，但实现不需要支持这种表示，在这种情况下 Number.MIN_VALUE 可能会更大。

¥Number.MIN_VALUE is the smallest positive number (not the most negative number) that can be represented within float precision — in other words, the number closest to 0. The ECMAScript spec doesn't define a precise value that implementations are required to support — instead the spec says, "must be the smallest non-zero positive value that can actually be represented by the implementation". This is because small IEEE-754 floating point numbers are denormalized, but implementations are not required to support this representation, in which case Number.MIN_VALUE may be larger.

实际上，它在 V8（Chrome、Edge、Node.js 使用）、SpiderMonkey（Firefox 使用）和 JavaScriptCore（Safari 使用）等主流引擎中的精确值为 2^-1074，或者 5E-324。

¥In practice, its precise value in mainstream engines like V8 (used by Chrome, Edge, Node.js), SpiderMonkey (used by Firefox), and JavaScriptCore (used by Safari) is 2^-1074, or 5E-324.

由于 MIN_VALUE 是 Number 的静态属性，因此你始终将其用作 Number.MIN_VALUE，而不是作为数字值的属性。

¥Because MIN_VALUE is a static property of Number, you always use it as Number.MIN_VALUE, rather than as a property of a number value.

¥Examples

¥Using MIN_VALUE

以下代码将两个数值相除。如果结果大于或等于 MIN_VALUE，则调用 func1 函数；否则，调用 func2 函数。

¥The following code divides two numeric values. If the result is greater than or equal to MIN_VALUE, the func1 function is called; otherwise, the func2 function is called.

if (num1 / num2 >= Number.MIN_VALUE) {
  func1();
} else {
  func2();
}

¥See also

• Number.MAX_VALUE