Number() constructor - JavaScript | MDN

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coerced to a number primitive

When Number() is called as a function (without new), it returns value coerced to a number primitive. Specially, BigInts values are converted to numbers instead of throwing. If value is absent, it becomes 0.

safely represented

Number() is the only case where a BigInt can be converted to a number without throwing, because it's very explicit.

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This page was last modified on Jul 10, 2025 by MDN contributors.

[Symbol.hasInstance]()

__defineGetter__()

__defineSetter__()

__lookupGetter__()

__lookupSetter__()

propertyIsEnumerable()

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