[Home](./index.md) > [@firebase/storage](./storage.md) > [UploadTaskSnapshot](./storage.uploadtasksnapshot.md) ## UploadTaskSnapshot interface Holds data about the current state of the upload task. Signature: ```typescript export interface UploadTaskSnapshot ``` ## Properties | Property | Type | Description | | --- | --- | --- | | [bytesTransferred](./storage.uploadtasksnapshot.bytestransferred.md) | number | The number of bytes that have been successfully uploaded so far. | | [metadata](./storage.uploadtasksnapshot.metadata.md) | [FullMetadata](./storage.fullmetadata.md) | Before the upload completes, contains the metadata sent to the server. After the upload completes, contains the metadata sent back from the server. | | [ref](./storage.uploadtasksnapshot.ref.md) | [StorageReference](./storage.storagereference.md) | The reference that spawned this snapshot's upload task. | | [state](./storage.uploadtasksnapshot.state.md) | [TaskState](./storage.taskstate.md) | The current state of the task. | | [task](./storage.uploadtasksnapshot.task.md) | [UploadTask](./storage.uploadtask.md) | The task of which this is a snapshot. | | [totalBytes](./storage.uploadtasksnapshot.totalbytes.md) | number | The total number of bytes to be uploaded. |