# QLThumbnailCreate(_:_:_:_:) Returns a thumbnail that’s generated in the background. ``` func QLThumbnailCreate(_ allocator: CFAllocator!, _ url: CFURL!, _ maxThumbnailSize: CGSize, _ options: CFDictionary!) -> Unmanaged! ``` ## Parameters `allocator` The allocator to use to create the thumbnail. `url` The URL of the document that you want to request a thumbnail for. `maxThumbnailSize` The maximum size in points for the thumbnail image. `options` Optional hints for creating a thumbnail image. Available options are [`kQLThumbnailOptionScaleFactorKey`](/documentation/QuickLook/kQLThumbnailOptionScaleFactorKey) and [`kQLThumbnailOptionIconModeKey`](/documentation/QuickLook/kQLThumbnailOptionIconModeKey). ## Return Value A generated thumbnail of the file at the provided `url`. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)