How to Check if a Variable Exists and is Initialized in JavaScript

General Discussions
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And here’s something I often layer on in more controlled setups: the good old truthy check.

if (myVar) {
  console.log("Yep, it's there and truthy!");
}

This style of javascript check if variable exists is super concise — but beware! It only works if myVar is already declared and holds a truthy value. So if it’s 0, false, null, or "", it’ll skip over. I usually reach for this in internal apps where the shape of the data is predictable and I just want to quickly verify meaningfulness without extra ceremony.