I exported an object on Blender.
The exported model file extension is fbx.
and I use FBXLoader to import the file on javascript.
    import { FBXLoader } from 'https://unpkg.com/three@0.145.0/examples/jsm/loaders/FBXLoader.js';
    const loader = new FBXLoader();
    loader.load( 'rect.fbx', function ( object ) {
      // center the model
      const box = new THREE.Box3().setFromObject( object );
      const center = box.getCenter( new THREE.Vector3() );
      object.position.x += ( object.position.x - center.x );
      object.position.y += ( object.position.y - center.y );
      object.position.z += ( object.position.z - center.z );
      scene.add( object );
    }, undefined, function ( error ) {
      console.error( error );
    } );
rect.fbx (4.0 KB)