# Serialized response formats

By default, the Object Storage API uses a `text/plain` response format. In addition, both JSON and XML data serialization response formats are supported.

To define the response format, use one of these methods:

Method | Description
--- | ---
format= `format` query parameter | Append this parameter to the URL for a `GET` request, where `format` is `json` or `xml`.

`Accept` request header

Include this header in the `GET` request. The valid header values are:

text/plain

  Plain text response format. The default.

application/jsontext

  JSON data serialization response format.

application/xml

  XML data serialization response format.

text/xml

  XML data serialization response format.

## Example 1. JSON example with format query parameter

For example, this request uses the `format` query parameter to ask for a JSON response:

    $ curl -i $publicURL?format=json -X GET -H "X-Auth-Token: $token"

    HTTP/1.1 200 OK
    Content-Length: 96
    X-Account-Object-Count: 1
    X-Timestamp: 1389453423.35964
    X-Account-Meta-Subject: Literature
    X-Account-Bytes-Used: 14
    X-Account-Container-Count: 2
    Content-Type: application/json; charset=utf-8
    Accept-Ranges: bytes
    X-Trans-Id: tx274a77a8975c4a66aeb24-0052d95365
    Date: Fri, 17 Jan 2014 15:59:33 GMT

Object Storage lists container names with additional information in JSON format:

    [
       {
          "count":0,
          "bytes":0,
          "name":"janeausten"
       },
       {
          "count":1,
          "bytes":14,
          "name":"marktwain"
       }
    ]

## Example 2. XML example with Accept header

This request uses the `Accept` request header to ask for an XML response:

    $ curl -i $publicURL -X GET -H "X-Auth-Token: $token" -H \
      "Accept: application/xml; charset=utf-8"

    HTTP/1.1 200 OK
    Content-Length: 263
    X-Account-Object-Count: 3
    X-Account-Meta-Book: MobyDick
    X-Timestamp: 1389453423.35964
    X-Account-Bytes-Used: 47
    X-Account-Container-Count: 2
    Content-Type: application/xml; charset=utf-8
    Accept-Ranges: bytes
    X-Trans-Id: txf0b4c9727c3e491694019-0052e03420
    Date: Wed, 22 Jan 2014 21:12:00 GMT

Object Storage lists container names with additional information in XML format:

    <?xml version="1.0" encoding="UTF-8"?>
    <account name="AUTH_73f0aa26640f4971864919d0eb0f0880">
        <container>
            <name>janeausten</name>
            <count>2</count>
            <bytes>33</bytes>
        </container>
        <container>
            <name>marktwain</name>
            <count>1</count>
            <bytes>14</bytes>
        </container>
    </account>

The remainder of the examples in this guide use standard, non-serialized responses. However, all `GET` requests that perform list operations accept the `format` query parameter or `Accept` request header.

this page last updated: 2026-08-18 20:34:00

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