What is the best way to use `javascript isObject` to check if a value is a real object?

General Discussions
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1

I’m working with an output that could be null, 0, or a JSON object, and I need to determine if it is indeed a valid object. Is there an isObject function like isArray in JavaScript, or is there another method to check if it’s an object?

2

I’ve hit this scenario many times while doing data validation in JS-heavy apps—here’s a quick manual check I’ve relied on:

function isObject(val) {
  return val !== null && typeof val === 'object' && !Array.isArray(val);
}

:white_check_mark: Why it works well:

  • Filters out null (since typeof null is 'object')
  • Excludes arrays
  • Focuses on plain objects only

If you’re just starting with javascript isobject checks, this approach is reliable and minimal.

3

Nice one, Priyanka. I’ve used a slightly stricter version when I needed bulletproof type checks across complex data inputs, especially when libraries or polyfills might override native behavior.

function isObject(val) {
  return Object.prototype.toString.call(val) === '[object Object]';
}

:white_check_mark: Why level it up?

  • Safer in edge cases where typeof might be overridden
  • Still avoids arrays and functions
  • Especially handy when dealing with sandboxed frames or unusual environments

If you’re deep-diving into javascript isobject logic and need something stricter for validation pipelines, this works great.

4

Totally agree with both of you! When working in larger codebases (or with data crossing between windows/iframes), I usually bring in Lodash-it’s just easier and saves time handling quirks.

_.isPlainObject(val);

:white_check_mark: Why use Lodash’s isPlainObject?

  • Handles cross-realm objects (like from iframes)
  • Ignores arrays, functions, class instances, etc.
  • Clean and production-safe

Yes, it does mean adding Lodash (npm install lodash), but if you’re already using it, this is probably the most robust way to handle javascript isobject checks without reinventing the wheel.