Why JavaScript forEach Doesn't Wait for Promises

A look at how async logic breaks inside forEach

Why JavaScript forEach Doesn’t Wait for Promises

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Many JavaScript developers bump into a strange issue at some point. They try using forEach with an async function, expecting it to wait on each await inside. Instead, it blows through the array instantly. This isn’t a bug or a quirk, it’s doing exactly what it was built to do. The way forEach works behind the scenes just doesn’t match how asynchronous code flows. To run asynchronous logic over arrays the way you want, you need to know how these pieces fit together.

How forEach Actually Works

The way forEach runs is clean and fast, but that speed can get in the way if you're working with anything asynchronous. You pass in a function, and it runs once per item in your array. But there’s no pause between those runs, no waiting, no promises tracked.

It Calls Your Function, Then Moves On

The forEach method doesn’t care what your function returns. It doesn’t pause to check if it’s waiting on something. It just loops through each value and calls the function with that value. If your callback is asynchronous, forEach still moves straight to the next one without waiting for the previous to finish.

Here’s a clear look:

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