Stay organized with collectionsSave and categorize content based on your preferences.
After uploading a file toCloud Storagereference, you can also get
and update the file metadata, for example to view or update the content type.
Files can also store custom key/value pairs with additional file metadata.
Get File Metadata
File metadata contains common properties such asname,size, andcontentType(often referred to as MIME type) in addition to some less
common ones likecontentDispositionandtimeCreated. This metadata can be
retrieved from aCloud Storagereference using
thegetMetadata()method.
Kotlin
// Create a storage reference from our appvalstorageRef=storage.reference// Get reference to the filevalforestRef=storageRef.child("images/forest.jpg")
forestRef.metadata.addOnSuccessListener{metadata->// Metadata now contains the metadata for 'images/forest.jpg'}.addOnFailureListener{// Uh-oh, an error occurred!}
// Create a storage reference from our appStorageReferencestorageRef=storage.getReference();// Get reference to the fileStorageReferenceforestRef=storageRef.child("images/forest.jpg");
forestRef.getMetadata().addOnSuccessListener(newOnSuccessListener<StorageMetadata>(){@OverridepublicvoidonSuccess(StorageMetadatastorageMetadata){// Metadata now contains the metadata for 'images/forest.jpg'}}).addOnFailureListener(newOnFailureListener(){@OverridepublicvoidonFailure(@NonNullExceptionexception){// Uh-oh, an error occurred!}});
You can update file metadata at any time after the file upload completes by
using theupdateMetadata()method. Refer to thefull listfor more information on what properties
can be updated. Only the properties specified in the metadata are updated,
all others are left unmodified.
Kotlin
// Create a storage reference from our appvalstorageRef=storage.reference// Get reference to the filevalforestRef=storageRef.child("images/forest.jpg")
// Create file metadata including the content typevalmetadata=storageMetadata{contentType="image/jpg"setCustomMetadata("myCustomProperty","myValue")}// Update metadata propertiesforestRef.updateMetadata(metadata).addOnSuccessListener{updatedMetadata->// Updated metadata is in updatedMetadata}.addOnFailureListener{// Uh-oh, an error occurred!}
// Create a storage reference from our appStorageReferencestorageRef=storage.getReference();// Get reference to the fileStorageReferenceforestRef=storageRef.child("images/forest.jpg");
// Create file metadata including the content typeStorageMetadatametadata=newStorageMetadata.Builder().setContentType("image/jpg").setCustomMetadata("myCustomProperty","myValue").build();// Update metadata propertiesforestRef.updateMetadata(metadata).addOnSuccessListener(newOnSuccessListener<StorageMetadata>(){@OverridepublicvoidonSuccess(StorageMetadatastorageMetadata){// Updated metadata is in storageMetadata}}).addOnFailureListener(newOnFailureListener(){@OverridepublicvoidonFailure(@NonNullExceptionexception){// Uh-oh, an error occurred!}});
You can delete writable metadata properties by passingnull:
Kotlin
// Create file metadata with property to deletevalmetadata=storageMetadata{contentType=null}// Delete the metadata propertyforestRef.updateMetadata(metadata).addOnSuccessListener{updatedMetadata->// updatedMetadata.contentType should be null}.addOnFailureListener{// Uh-oh, an error occurred!}
// Create file metadata with property to deleteStorageMetadatametadata=newStorageMetadata.Builder().setContentType(null).build();// Delete the metadata propertyforestRef.updateMetadata(metadata).addOnSuccessListener(newOnSuccessListener<StorageMetadata>(){@OverridepublicvoidonSuccess(StorageMetadatastorageMetadata){// metadata.contentType should be null}}).addOnFailureListener(newOnFailureListener(){@OverridepublicvoidonFailure(@NonNullExceptionexception){// Uh-oh, an error occurred!}});
There are a number of reasons why errors may occur on getting or updating
metadata, including the file not existing, or the user not having permission
to access the desired file. More information on errors can be found in theHandle Errorssection of the docs.
Custom Metadata
You can specify custom metadata using thesetCustomMetadata()method in theStorageMetadata.Builderclass.
Kotlin
valmetadata=storageMetadata{setCustomMetadata("location","Yosemite, CA, USA")setCustomMetadata("activity","Hiking")}
You can store app-specific data for each file in custom metadata, but we highly
recommend using a database (such as theFirebase Realtime Database)
to store and synchronize this type of data.
File Metadata Properties
A full list of metadata properties on a file is available below:
Property Getter
Type
Setter Exists
getBucket
String
NO
getGeneration
String
NO
getMetadataGeneration
String
NO
getPath
String
NO
getName
String
NO
getSizeBytes
long
NO
getCreationTimeMillis
long
NO
getUpdatedTimeMillis
long
NO
getMd5Hash
String
NO
getCacheControl
String
YES
getContentDisposition
String
YES
getContentEncoding
String
YES
getContentLanguage
String
YES
getContentType
String
YES
getCustomMetadata
String
YES
getCustomMetadataKeys
Set<String>
NO
Uploading, downloading, and updating files is important, but so is being able
to remove them. Let's learn how todelete filesfromCloud Storage.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[],[],null,["\u003cbr /\u003e\n\nAfter uploading a file to Cloud Storage reference, you can also get\nand update the file metadata, for example to view or update the content type.\nFiles can also store custom key/value pairs with additional file metadata.\n| **Note:** By default, a Cloud Storage for Firebase bucket requires Firebase Authentication to perform any action on the bucket's data or files. You can change your Firebase Security Rules for Cloud Storage to [allow unauthenticated access for specific situations](/docs/storage/security/rules-conditions#public). However, for most situations, we strongly recommend [restricting access and setting up robust security rules](/docs/storage/security/get-started) (especially for production apps). Note that if you use Google App Engine and have a default Cloud Storage bucket with a name format of `*.appspot.com`, you may need to consider [how your security rules impact access to App Engine files](/docs/storage/gcp-integration#security-rules-and-app-engine-files).\n\nGet File Metadata\n\nFile metadata contains common properties such as `name`, `size`, and\n`contentType` (often referred to as MIME type) in addition to some less\ncommon ones like `contentDisposition` and `timeCreated`. This metadata can be\nretrieved from a Cloud Storage reference using\nthe `getMetadata()` method. \n\nKotlin \n\n```kotlin\n// Create a storage reference from our app\nval storageRef = storage.reference\n\n// Get reference to the file\nval forestRef = storageRef.child(\"images/forest.jpg\")\n``` \n\n```kotlin\nforestRef.metadata.addOnSuccessListener { metadata -\u003e\n // Metadata now contains the metadata for 'images/forest.jpg'\n}.addOnFailureListener {\n // Uh-oh, an error occurred!\n}https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/kotlin/StorageActivity.kt#L345-L349\n```\n\nJava \n\n```java\n// Create a storage reference from our app\nStorageReference storageRef = storage.getReference();\n\n// Get reference to the file\nStorageReference forestRef = storageRef.child(\"images/forest.jpg\");\n``` \n\n```java\nforestRef.getMetadata().addOnSuccessListener(new OnSuccessListener\u003cStorageMetadata\u003e() {\n @Override\n public void onSuccess(StorageMetadata storageMetadata) {\n // Metadata now contains the metadata for 'images/forest.jpg'\n }\n}).addOnFailureListener(new OnFailureListener() {\n @Override\n public void onFailure(@NonNull Exception exception) {\n // Uh-oh, an error occurred!\n }\n});https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/StorageActivity.java#L437-L447\n```\n\nUpdate File Metadata\n\nYou can update file metadata at any time after the file upload completes by\nusing the `updateMetadata()` method. Refer to the\n[full list](#file-metadata-properties) for more information on what properties\ncan be updated. Only the properties specified in the metadata are updated,\nall others are left unmodified. \n\nKotlin \n\n```kotlin\n// Create a storage reference from our app\nval storageRef = storage.reference\n\n// Get reference to the file\nval forestRef = storageRef.child(\"images/forest.jpg\")\n``` \n\n```kotlin\n// Create file metadata including the content type\nval metadata = storageMetadata {\n contentType = \"image/jpg\"\n setCustomMetadata(\"myCustomProperty\", \"myValue\")\n}\n\n// Update metadata properties\nforestRef.updateMetadata(metadata).addOnSuccessListener { updatedMetadata -\u003e\n // Updated metadata is in updatedMetadata\n}.addOnFailureListener {\n // Uh-oh, an error occurred!\n}https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/kotlin/StorageActivity.kt#L353-L364\n```\n\nJava \n\n```java\n// Create a storage reference from our app\nStorageReference storageRef = storage.getReference();\n\n// Get reference to the file\nStorageReference forestRef = storageRef.child(\"images/forest.jpg\");\n``` \n\n```java\n// Create file metadata including the content type\nStorageMetadata metadata = new StorageMetadata.Builder()\n .setContentType(\"image/jpg\")\n .setCustomMetadata(\"myCustomProperty\", \"myValue\")\n .build();\n\n// Update metadata properties\nforestRef.updateMetadata(metadata)\n .addOnSuccessListener(new OnSuccessListener\u003cStorageMetadata\u003e() {\n @Override\n public void onSuccess(StorageMetadata storageMetadata) {\n // Updated metadata is in storageMetadata\n }\n })\n .addOnFailureListener(new OnFailureListener() {\n @Override\n public void onFailure(@NonNull Exception exception) {\n // Uh-oh, an error occurred!\n }\n });https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/StorageActivity.java#L451-L470\n```\n\nYou can delete writable metadata properties by passing `null`: \n\nKotlin \n\n```kotlin\n// Create file metadata with property to delete\nval metadata = storageMetadata {\n contentType = null\n}\n\n// Delete the metadata property\nforestRef.updateMetadata(metadata).addOnSuccessListener { updatedMetadata -\u003e\n // updatedMetadata.contentType should be null\n}.addOnFailureListener {\n // Uh-oh, an error occurred!\n}https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/kotlin/StorageActivity.kt#L374-L384\n```\n\nJava \n\n```java\n// Create file metadata with property to delete\nStorageMetadata metadata = new StorageMetadata.Builder()\n .setContentType(null)\n .build();\n\n// Delete the metadata property\nforestRef.updateMetadata(metadata)\n .addOnSuccessListener(new OnSuccessListener\u003cStorageMetadata\u003e() {\n @Override\n public void onSuccess(StorageMetadata storageMetadata) {\n // metadata.contentType should be null\n }\n })\n .addOnFailureListener(new OnFailureListener() {\n @Override\n public void onFailure(@NonNull Exception exception) {\n // Uh-oh, an error occurred!\n }\n });https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/StorageActivity.java#L480-L498\n```\n\nHandle Errors\n\nThere are a number of reasons why errors may occur on getting or updating\nmetadata, including the file not existing, or the user not having permission\nto access the desired file. More information on errors can be found in the\n[Handle Errors](/docs/storage/android/handle-errors)\nsection of the docs.\n\nCustom Metadata\n\nYou can specify custom metadata using the `setCustomMetadata()` method in the\n`StorageMetadata.Builder` class. \n\nKotlin \n\n```kotlin\nval metadata = storageMetadata {\n setCustomMetadata(\"location\", \"Yosemite, CA, USA\")\n setCustomMetadata(\"activity\", \"Hiking\")\n}https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/kotlin/StorageActivity.kt#L390-L393\n```\n\nJava \n\n```java\nStorageMetadata metadata = new StorageMetadata.Builder()\n .setCustomMetadata(\"location\", \"Yosemite, CA, USA\")\n .setCustomMetadata(\"activity\", \"Hiking\")\n .build();https://github.com/firebase/snippets-android/blob/b694d4dbd411d31be39655f47691c3e9f3529b03/storage/app/src/main/java/com/google/firebase/referencecode/storage/StorageActivity.java#L504-L507\n```\n\nYou can store app-specific data for each file in custom metadata, but we highly\nrecommend using a database (such as the\n[Firebase Realtime Database](/docs/database/android/start))\nto store and synchronize this type of data.\n\nFile Metadata Properties\n\nA full list of metadata properties on a file is available below:\n\n| Property Getter | Type | Setter Exists |\n|-------------------------|---------------|---------------|\n| `getBucket` | `String` | NO |\n| `getGeneration` | `String` | NO |\n| `getMetadataGeneration` | `String` | NO |\n| `getPath` | `String` | NO |\n| `getName` | `String` | NO |\n| `getSizeBytes` | `long` | NO |\n| `getCreationTimeMillis` | `long` | NO |\n| `getUpdatedTimeMillis` | `long` | NO |\n| `getMd5Hash` | `String` | NO |\n| `getCacheControl` | `String` | YES |\n| `getContentDisposition` | `String` | YES |\n| `getContentEncoding` | `String` | YES |\n| `getContentLanguage` | `String` | YES |\n| `getContentType` | `String` | YES |\n| `getCustomMetadata` | `String` | YES |\n| `getCustomMetadataKeys` | `Set\u003cString\u003e` | NO |\n\nUploading, downloading, and updating files is important, but so is being able\nto remove them. Let's learn how to\n[delete files](/docs/storage/android/delete-files)\nfrom Cloud Storage."]]
