MDN’s new design is in Beta! A sneak peek:

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The WebAssembly.imports() function returns an array containing descriptions of all the declared imports of the given Module.


var custSec = WebAssembly.Module.imports(module);


A WebAssembly.Module object.

Return value

An array containing objects representing the imported functions of the given module.


If module is not a WebAssembly.Module object instance, a TypeError is thrown.


The following example (see imports.html source code; see it live also) compiles the loaded simple.wasm module.  This module is then queried for its imports.

fetch('simple.wasm').then(response =>
).then(bytes =>
).then(function(mod) {
  var imports = WebAssembly.Module.imports(mod);

The output looks like this:

{ module: "imports", name: "imported_func", kind: "function" }


Specification Status Comment
Web Assembly JavaScript API
The definition of 'imports()' in that specification.
Draft Initial draft definition.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 57 15[2] 52 (52)[1] No support 44 11
Feature Chrome for Android Android Webview Edge Mobile Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 57 57 No support 52.0 (52)[1] No support No support 11

[1] WebAssembly is enabled in Firefox 52+, although disabled in the Firefox 52 Extended Support Release (ESR.)

[2] Currently supported behind the “Experimental JavaScript Features” flag. See this blog post for more details.

See also

Document Tags and Contributors

 Contributors to this page: syu_kato, chrisdavidmills, lukewagner, fscholz, svodnik
 Last updated by: syu_kato,