For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt, and this page is available as Markdown at /reference/object/mapValues.md.
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    mapValues es-toolkit

    Returns a new object with values transformed through a function.

    const newObj = mapValues(object, getNewValue);

    Usage

    mapValues(object, getNewValue)

    Use mapValues when you want to create a new object by transforming each value. Keys remain the same, and only the values are changed to the results of the getNewValue function.

    import { mapValues } from 'es-toolkit/object';

// Double all values
const numbers = { a: 1, b: 2, c: 3 };
const doubled = mapValues(numbers, value => value * 2);
// doubled becomes { a: 2, b: 4, c: 6 }

// Convert string values to uppercase
const strings = { first: 'hello', second: 'world' };
const uppercased = mapValues(strings, value => value.toUpperCase());
// uppercased becomes { first: 'HELLO', second: 'WORLD' }

// Use both key and value
const scores = { alice: 85, bob: 90, charlie: 95 };
const grades = mapValues(scores, (value, key) => `${key}: ${value >= 90 ? 'A' : 'B'}`);
// grades becomes { alice: 'alice: B', bob: 'bob: A', charlie: 'charlie: A' }

    Parameters

    objectT extends objectrequired

    The object to transform values from.

    getNewValue(value: T[K], key: K, object: T) => Vrequired

    A function that generates new values. Receives value, key, and the entire object as parameters.

    Returns

    Returns a new object with transformed values.

    Record<K, V>
    Source: es-toolkit

    Re-exported verbatim from es-toolkit. Implementation, edge cases, and performance behavior are owned upstream. This page mirrors the documentation at the pinned version; the linked source is authoritative.