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/omitBy.md.
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    omitBy es-toolkit

    Returns a new object containing only the properties that do not satisfy the condition function.

    const result = omitBy(obj, shouldOmit);

    Usage

    omitBy(obj, shouldOmit)

    Use omitBy when you want to selectively exclude properties from an object based on a condition function. Properties for which the condition function returns true are excluded, and only properties that return false are included in the new object.

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

// Exclude properties with string values
const obj = { a: 1, b: 'remove', c: 3, d: 'also remove' };
const result = omitBy(obj, value => typeof value === 'string');
// result is { a: 1, c: 3 }

// Exclude only even values
const numbers = { a: 1, b: 2, c: 3, d: 4 };
const odds = omitBy(numbers, value => value % 2 === 0);
// odds is { a: 1, c: 3 }

// Use both key and value
const data = { user1: 25, user2: 17, admin1: 30, admin2: 28 };
const nonAdmins = omitBy(data, (value, key) => key.startsWith('admin'));
// nonAdmins is { user1: 25, user2: 17 }

    Parameters

    objT extends Record<string, any>required

    The object to filter properties from.

    shouldOmit(value: T[keyof T], key: keyof T) => booleanrequired

    A condition function that determines whether to exclude a property. Receives the value and key, and returns true to exclude, false to keep.

    Returns

    A new object consisting of properties that do not satisfy the condition function.

    Partial<T>
    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.