Lodash _.isString() Method

Beginner
5 min read
Updated: Nov 2026
5 examples
Lang
Decorative image with the word ISSTRING

Definition

Checks if value is classified as a string primitive or String object. Part of Lodash Lang since 0.1.0 (stable — not deprecated).

Note: Empty "" still counts as a string. Prefer string primitives in new code; boxed new String(...) is rare.

Syntax

Call _.isString. Start with this line.

Lodash
_.isString(value)
CallWhat it does
_.isString(value)Primary signature.

Prefer import isString from "lodash/isString" when you want a smaller bundle.

Library declarations
Lodash
_.isString(value)

Parameters

ParameterDescription
valueRequired. The value to check

Return Value

Return ValueDescription
*true if string, else false

Lodash Examples

Example 1 — Official: 'abc'

A string primitive is classified as a string.

Lodash
_.isString('abc');
// → true
Try It Yourself

How It Works

  1. Input. Official sample: the primitive 'abc'.
  2. Type. typeof 'abc' === "string".
  3. Result. Returns true.
  4. Use. Guard text fields before calling string methods.

Example 2 — Official: Number 1

Numbers are not strings — even when they look like text.

Lodash
_.isString(1);
// → false
Try It Yourself

How It Works

  1. Input. The number 1 from the official docs.
  2. Wrong type. It is a number, not text.
  3. Result. Returns false.
  4. Tip. Use '1' or String(1) when you need a string.

Example 3 — Empty String

Blank text is still a string — falsy, but typed correctly.

Lodash
_.isString('');
// → true

_.isString(' ');
// → true
Try It Yourself

How It Works

  1. Empty. "" has type string.
  2. Whitespace. A space is also a string.
  3. Both pass. Type check ≠ “has content?”.
  4. Validate. Use .trim().length when blanks are invalid.

Example 4 — Boxed String Object

Lodash also accepts new String(...); typeof alone does not.

Lodash
var boxed = new String('abc');

_.isString(boxed);           // → true
typeof boxed === "string";   // → false  (typeof is "object")
Try It Yourself

How It Works

  1. Boxed. new String('abc') is a String object.
  2. isString. Lodash classifies it as string → true.
  3. typeof. Reports "object" → fails a naive check.
  4. Prefer. Use primitives ('abc') in new code.

Example 5 — Common Non-Strings

Values that often show up near text fields but are not strings.

Lodash
_.isString(null);       // → false
_.isString(true);       // → false
_.isString(['a']);      // → false
_.isString(undefined);  // → false
Try It Yourself

How It Works

  1. nullish. Use _.isNil for missing values.
  2. Boolean. Use _.isBoolean.
  3. Array. One-element arrays are still arrays.
  4. Rule. Only string-branded values pass.
Compatibility

Browser & Runtime Support

_.isString is a Lodash Lang helper (available since 0.1.0, stable in 4.x). It runs anywhere Lodash runs — modern browsers (via CDN or bundle) and Node.js / Bun / Deno with npm install lodash.

✓ Stable · Lodash 0.1.0+

_.isString()

Available in [email protected] full builds and the lodash/isString modular import. Works in evergreen browsers and current Node LTS when Lodash is installed.

100% With Lodash 4.x
Google Chrome Supported · Desktop & Mobile
Full support
Mozilla Firefox Supported · Desktop & Mobile
Full support
Apple Safari Supported · macOS & iOS
Full support
Microsoft Edge Supported · Chromium
Full support
Internet Explorer No native support · Use a polyfill
Polyfill
Opera Supported · Modern versions
Full support
Samsung Internet Supported · Android
Full support
Bun Supported · JavaScript runtime
Supported
Deno Supported · JavaScript runtime
Supported
Node.js Supported · Server runtime
Supported
Android WebView Supported · Modern WebView
Full support
_.isString Lodash 0.1.0+

Bottom line: Safe for production once Lodash is on the page or in your bundle. Prefer import isString from "lodash/isString" for smaller builds. For primitives only, typeof value === "string" is enough.

Frequently Asked Questions

_.isString(value) returns true if value is a string primitive or a boxed String object. Numbers, booleans, null, arrays, and other types return false.
Yes. "" is still a valid string. Combine with a length check if you also require non-empty input.
Boxed String objects have typeof "object", but Lodash recognizes the [object String] brand and returns true — matching the docs intent for string classification.
typeof only catches primitives. _.isString also accepts rare String objects. Prefer primitives in new code; use _.isString when you must accept both.
Template literals evaluate to plain strings, so _.isString(`hi`) returns true.
Use import isString from "lodash/isString" or require("lodash/isString"). Full build: import _ from "lodash" then _.isString.

Next: _.isSymbol()

Check whether a value is classified as a Symbol.

_.isSymbol() tutorial →

About the author

Mari Selvan M P
Mari Selvan M P 🔗

Developer, cloud engineer, and technical writer

  • Experience 12 years building web and cloud systems
  • Focus Full Stack Development, AWS, and Developer Education

I write practical tutorials so students and working developers can learn by doing—from databases and APIs to deployment on AWS.

AWS Certified Developer – Associate (Credly)

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