# QueryVectors
<a name="API_S3VectorBuckets_QueryVectors"></a>

Performs an approximate nearest neighbor search query in a vector index using a query vector. By default, it returns the keys of approximate nearest neighbors. You can optionally include the computed distance (between the query vector and each vector in the response), the vector data, and metadata of each vector in the response. 

To specify the vector index, you can either use both the vector bucket name and the vector index name, or use the vector index Amazon Resource Name (ARN). 

Permissions  
You must have the `s3vectors:QueryVectors` permission to use this operation. Additional permissions are required based on the request parameters you specify:  
+ With only `s3vectors:QueryVectors` permission, you can retrieve vector keys of approximate nearest neighbors and computed distances between these vectors. This permission is sufficient only when you don't set any metadata filters and don't request vector data or metadata (by keeping the `returnMetadata` parameter set to `false` or not specified).
+ If you specify a metadata filter or set `returnMetadata` to true, you must have both `s3vectors:QueryVectors` and `s3vectors:GetVectors` permissions. The request fails with a `403 Forbidden error` if you request metadata filtering, vector data, or metadata without the `s3vectors:GetVectors` permission.

## Request Syntax
<a name="API_S3VectorBuckets_QueryVectors_RequestSyntax"></a>

```
POST /QueryVectors HTTP/1.1
Content-type: application/json

{
   "filter": JSON value,
   "indexArn": "string",
   "indexName": "string",
   "queryVector": { ... },
   "returnDistance": boolean,
   "returnMetadata": boolean,
   "topK": number,
   "vectorBucketName": "string"
}
```

## URI Request Parameters
<a name="API_S3VectorBuckets_QueryVectors_RequestParameters"></a>

The request does not use any URI parameters.

## Request Body
<a name="API_S3VectorBuckets_QueryVectors_RequestBody"></a>

The request accepts the following data in JSON format.

 ** [filter](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-filter"></a>
Metadata filter to apply during the query. For more information about metadata keys, see [Metadata filtering](https://docs.aws.amazon.com/AmazonS3/latest/userguide/s3-vectors-metadata-filtering.html) in the *Amazon S3 User Guide*.   
Type: JSON value  
Required: No

 ** [indexArn](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-indexArn"></a>
The ARN of the vector index that you want to query.  
Type: String  
Pattern: `arn:aws[-a-z0-9]*:s3vectors:[a-z0-9-]+:[0-9]{12}:bucket/[a-z0-9][a-z0-9-.]{1,61}[a-z0-9]/index/[a-z0-9][a-z0-9-.]{1,61}[a-z0-9]`   
Required: No

 ** [indexName](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-indexName"></a>
The name of the vector index that you want to query.   
Type: String  
Length Constraints: Minimum length of 3. Maximum length of 63.  
Required: No

 ** [queryVector](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-queryVector"></a>
The query vector. Ensure that the query vector has the same dimension as the dimension of the vector index that's being queried. For example, if your vector index contains vectors with 384 dimensions, your query vector must also have 384 dimensions.   
Type: [VectorData](API_S3VectorBuckets_VectorData.md) object  
 **Note: **This object is a Union. Only one member of this object can be specified or returned.  
Required: Yes

 ** [returnDistance](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-returnDistance"></a>
Indicates whether to include the computed distance in the response. The default value is `false`.  
Type: Boolean  
Required: No

 ** [returnMetadata](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-returnMetadata"></a>
Indicates whether to include metadata in the response. The default value is `false`.  
Type: Boolean  
Required: No

 ** [topK](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-topK"></a>
The number of results to return for each query.  
Type: Integer  
Valid Range: Minimum value of 1.  
Required: Yes

 ** [vectorBucketName](#API_S3VectorBuckets_QueryVectors_RequestSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-request-vectorBucketName"></a>
The name of the vector bucket that contains the vector index.   
Type: String  
Length Constraints: Minimum length of 3. Maximum length of 63.  
Required: No

## Response Syntax
<a name="API_S3VectorBuckets_QueryVectors_ResponseSyntax"></a>

```
HTTP/1.1 200
Content-type: application/json

{
   "distanceMetric": "string",
   "vectors": [ 
      { 
         "distance": number,
         "key": "string",
         "metadata": JSON value
      }
   ]
}
```

## Response Elements
<a name="API_S3VectorBuckets_QueryVectors_ResponseElements"></a>

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

 ** [distanceMetric](#API_S3VectorBuckets_QueryVectors_ResponseSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-response-distanceMetric"></a>
The distance metric that was used for the similarity search calculation. This is the same distance metric that was configured for the vector index when it was created.  
Type: String  
Valid Values: `euclidean | cosine` 

 ** [vectors](#API_S3VectorBuckets_QueryVectors_ResponseSyntax) **   <a name="AmazonS3-S3VectorBuckets_QueryVectors-response-vectors"></a>
The vectors in the approximate nearest neighbor search.  
Type: Array of [QueryOutputVector](API_S3VectorBuckets_QueryOutputVector.md) objects

## Errors
<a name="API_S3VectorBuckets_QueryVectors_Errors"></a>

 ** AccessDeniedException **   
Access denied.  
HTTP Status Code: 403

 ** InternalServerException **   
The request failed due to an internal server error.  
HTTP Status Code: 500

 ** KmsDisabledException **   
The specified AWS KMS key isn't enabled.  
HTTP Status Code: 400

 ** KmsInvalidKeyUsageException **   
The request was rejected for one of the following reasons:   
+ The `KeyUsage` value of the KMS key is incompatible with the API operation.
+ The encryption algorithm or signing algorithm specified for the operation is incompatible with the type of key material in the KMS key (`KeySpec`).
For more information, see [InvalidKeyUsageException](https://docs.aws.amazon.com/kms/latest/APIReference/API_Encrypt.html#API_Encrypt_Errors) in the * AWS Key Management Service API Reference*.  
HTTP Status Code: 400

 ** KmsInvalidStateException **   
The key state of the KMS key isn't compatible with the operation.  
For more information, see [KMSInvalidStateException](https://docs.aws.amazon.com/kms/latest/APIReference/API_Encrypt.html#API_Encrypt_Errors) in the * AWS Key Management Service API Reference*.  
HTTP Status Code: 400

 ** KmsNotFoundException **   
The KMS key can't be found.  
HTTP Status Code: 400

 ** NotFoundException **   
The request was rejected because the specified resource can't be found.  
HTTP Status Code: 404

 ** RequestTimeoutException **   
The request timed out. Retry your request.  
HTTP Status Code: 408

 ** ServiceUnavailableException **   
The service is unavailable. Wait briefly and retry your request. If it continues to fail, increase your waiting time between retries.  
HTTP Status Code: 503

 ** TooManyRequestsException **   
The request was denied due to request throttling.  
HTTP Status Code: 429

 ** ValidationException **   
The requested action isn't valid.    
 ** fieldList **   
A list of specific validation failures that are encountered during input processing. Each entry in the list contains a path to the field that failed validation and a detailed message that explains why the validation failed. To satisfy multiple constraints, a field can appear multiple times in this list if it failed. You can use the information to identify and fix the specific validation issues in your request.
HTTP Status Code: 400

## See Also
<a name="API_S3VectorBuckets_QueryVectors_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/s3vectors-2025-07-15/QueryVectors) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/s3vectors-2025-07-15/QueryVectors)