strip-undefined-values

Remove undefined values from an object before sending to APIs, databases, or serializers.

Zero dependencies. Fully typed. Tiny. Shallow.

import { stripUndefined } from "strip-undefined-values"

stripUndefined({ name: "Tomas", age: undefined, active: true })
// => { name: "Tomas", active: true }

Installation

npm install strip-undefined-values

pnpm add strip-undefined-values

yarn add strip-undefined-values

API

function stripUndefined<T extends Record<string, any>>(obj: T): StripUndefined<T>

Removes own properties whose value is strictly undefined. Returns a new object — does not mutate the input. Nested objects are not traversed (shallow only).

| Value | Kept? | | ----------- | ----- | | null | Yes | | false | Yes | | 0 | Yes | | "" | Yes | | NaN | Yes | | undefined | No|

TypeScript

The return type StripUndefined<T> automatically excludes keys whose type includes undefined:

type Input = { name: string; age: number | undefined; active: boolean }
type Output = StripUndefined<Input>
//   ^? { name: string; active: boolean }

This is intentionally conservative — the type is stricter than runtime so you can never accidentally access a possibly-undefined property on the result.

You can also use StripUndefined<T> standalone as a utility type:

import type { StripUndefined } from "strip-undefined-values"

Common Use Cases

API payloads / PATCH requests

const body = stripUndefined({ name: "Tomas", email: "[email protected]", age: undefined })
// => { name: "Tomas", email: "[email protected]" }

Query parameters

const params = stripUndefined({ page, search, sort })
const url = `/items?${new URLSearchParams(params)}`

Prisma / database updates

await prisma.user.update({
  where: { id },
  data: stripUndefined({ name, email, bio })
})

GraphQL variables

const { data } = await client.query({
  query: GET_USERS,
  variables: stripUndefined({ first, after, filter })
})

Optional form fields

const formData = stripUndefined({
  title: form.title,
  description: form.description || undefined,
  category: form.category || undefined,
})

Comparison

| Approach | Typed? | Deps | Deep? | Mutates? | | --- | --- | --- | --- | --- | | strip-undefined-values | Yes | 0 | No | No | | lodash.omitBy | Partial | 1 | No | No | | Object.fromEntries(…filter…) | No | 0 | No | No | | remove-undefined-objects | No | 1+ | Yes | No | | Manual delete | No | 0 | No | Yes |

License

MIT