YouTube Data API Overview

Introduction

This document is intended for developers who want to write applications that interact with YouTube. It explains basic concepts of YouTube and of the API itself. It also provides an overview of the different functions that the API supports.

Before you start

1. You need a Google Account to access the Google API Console, request an API key, and register your application.

2. Create a project in the Google Developers Console and obtain authorization credentials so your application can submit API requests.

3. After creating your project, make sure the YouTube Data API is one of the services that your application is registered to use:

   1. Go to the API Console and select the project that you just registered.
   2. Visit the Enabled APIs page. In the list of APIs, make sure the status is ON for the YouTube Data API v3.

4. If your application will use any API methods that require user authorization, read the authentication guide to learn how to implement OAuth 2.0 authorization.

5. Select a client library to simplify your API implementation.

6. Familiarize yourself with the core concepts of the JSON (JavaScript Object Notation) data format. JSON is a common, language-independent data format that provides a simple text representation of arbitrary data structures. For more information, see json.org.

Resources and resource types

A resource is an individual data entity with a unique identifier. The table below describes the different types of resources that you can interact with using the API.

Note that, in many cases, a resource contains references to other resources. For example, a playlistItem resource's snippet.resourceId.videoId property identifies a video resource that, in turn, contains complete information about the video. As another example, a search result contains either a videoId, playlistId, or channelId property that identifies a particular video, playlist, or channel resource.

Supported operations

The following table shows the most common methods that the API supports. Some resources also support other methods that perform functions more specific to those resources. For example, the videos.rate method associates a user rating with a video, and the thumbnails.set method uploads a video thumbnail image to YouTube and associates it with a video.

The API currently supports methods to list each of the supported resource types, and it supports write operations for many resources as well.

The table below identifies the operations that are supported for different types of resources. Operations that insert, update, or delete resources always require user authorization. In some cases, list methods support both authorized and unauthorized requests, where unauthorized requests only retrieve public data while authorized requests can also retrieve information about or private to the currently authenticated user.

Quota usage

The YouTube Data API uses a quota to ensure that developers use the service as intended and do not create applications that unfairly reduce service quality or limit access for others. All API requests, including invalid requests, incur at least a one-point quota cost. You can find the quota available to your application in the API Console.

Projects that enable the YouTube Data API have a default quota allocation of 10,000 units per day, an amount sufficient for the overwhelming majority of our API users. Default quota, which is subject to change, helps us optimize quota allocations and scale our infrastructure in a way that is more meaningful to our API users. You can see your quota usage on the Quotas page in the API Console.

Note: If you reach the quota limit, you can request additional quota by completing the Quota extension request form for YouTube API Services.

Calculating quota usage

Google calculates your quota usage by assigning a cost to each request. Different types of operations have different quota costs. For example:

• A read operation that retrieves a list of resources -- channels, videos, playlists -- usually costs 1 unit.
• A write operation that creates, updates, or deletes a resource usually has costs 50 units.
• A search request costs 100 units.
• A video upload costs 1600 units.

The Quota costs for API requests table shows the quota cost of each API method. With these rules in mind, you can estimate the number of requests that your application could send per day without exceeding your quota.

Partial resources

The API allows, and actually requires, the retrieval of partial resources so that applications avoid transferring, parsing, and storing unneeded data. This approach also ensures that the API uses network, CPU, and memory resources more efficiently.

The API supports two request parameters, which are explained in the following sections, that enable you to identify the resource properties that should be included in API responses.

• The part parameter identifies groups of properties that should be returned for a resource.
• The fields parameter filters the API response to only return specific properties within the requested resource parts.

How to use the part parameter

The part parameter is a required parameter for any API request that retrieves or returns a resource. The parameter identifies one or more top-level (non-nested) resource properties that should be included in an API response. For example, a video resource has the following parts:

• snippet
• contentDetails
• fileDetails
• player
• processingDetails
• recordingDetails
• statistics
• status
• suggestions
• topicDetails

All of these parts are objects that contain nested properties, and you can think of these objects as groups of metadata fields that the API server might (or might not) retrieve. As such, the part parameter requires you to select the resource components that your application actually uses. This requirement serves two key purposes:

• It reduces latency by preventing the API server from spending time retrieving metadata fields that your application doesn't use.
• It reduces bandwidth usage by reducing (or eliminating) the amount of unnecessary data that your application might retrieve.

Over time, as resources add more parts, these benefits will only increase since your application will not be requesting newly introduced properties that it doesn't support.

How to use the fields parameter

The fields parameter filters the API response, which only contains the resource parts identified in the part parameter value, so that the response only includes a specific set of fields. The fields parameter lets you remove nested properties from an API response and thereby further reduce your bandwidth usage. (The part parameter cannot be used to filter nested properties from a response.)

The following rules explain the supported syntax for the fields parameter value, which is loosely based on XPath syntax:

• Use a comma-separated list (fields=a,b) to select multiple fields.
• Use an asterisk (fields=*) as a wildcard to identify all fields.
• Use parentheses (fields=a(b,c)) to specify a group of nested properties that will be included in the API response.
• Use a forward slash (fields=a/b) to identify a nested property.

In practice, these rules often allow several different fields parameter values to retrieve the same API response. For example, if you want to retrieve the playlist item ID, title, and position for every item in a playlist, you could use any of the following values:

• fields=items/id,playlistItems/snippet/title,playlistItems/snippet/position
• fields=items(id,snippet/title,snippet/position)
• fields=items(id,snippet(title,position))

Note: As with all query parameter values, the fields parameter value must be URL encoded. For better readability, the examples in this document omit the encoding.

Sample partial requests

The examples below demonstrate how you can use the part and fields parameters to ensure that API responses only include the data that your application uses:

1. Example 1 returns a video resource that includes four parts as well as kind and etag properties.
2. Example 2 returns a video resource that includes two parts as well as kind and etag properties.
3. Example 3 returns a video resource that includes two parts but excludes kind and etag properties.
4. Example 4 returns a video resource that includes two parts but excludes kind and etag as well as some nested properties in the resource's snippet object.

URL: https://www.googleapis.com/youtube/v3/videos?id=7lCDEYXw3mM&key=YOUR_API_KEY
     &part=snippet,contentDetails,statistics,status

Description: This example retrieves a video resource and identifies several
             resource parts that should be included in the API response.

API response:

{ 
 "kind": "youtube#videoListResponse",
 "etag": "\"UCBpFjp2h75_b92t44sqraUcyu0/sDAlsG9NGKfr6v5AlPZKSEZdtqA\"",
 "videos": [
  {
   "id": "7lCDEYXw3mM",
   "kind": "youtube#video",
   "etag": "\"UCBpFjp2h75_b92t44sqraUcyu0/iYynQR8AtacsFUwWmrVaw4Smb_Q\"",
   "snippet": { 
    "publishedAt": "2012-06-20T22:45:24.000Z",
    "channelId": "UC_x5XG1OV2P6uZZ5FSM9Ttw",
    "title": "Google I/O 101: Q&A On Using Google APIs",
    "description": "Antonio Fuentes speaks to us and takes questions on working with Google APIs and OAuth 2.0.",
    "thumbnails": {
     "default": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/default.jpg"
     },
     "medium": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/mqdefault.jpg"
     },
     "high": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/hqdefault.jpg"
     }
    },
    "categoryId": "28"
   },
   "contentDetails": {
    "duration": "PT15M51S",
    "aspectRatio": "RATIO_16_9"
   },
   "statistics": {
    "viewCount": "3057",
    "likeCount": "25",
    "dislikeCount": "0",
    "favoriteCount": "17",
    "commentCount": "12"
   },
   "status": {
    "uploadStatus": "STATUS_PROCESSED",
    "privacyStatus": "PRIVACY_PUBLIC"
   }
  }
 ]
}

URL: https://www.googleapis.com/youtube/v3/videos?id=7lCDEYXw3mM&key=YOUR_API_KEY
     &part=snippet,statistics

Description: This example modifies the part parameter value so that the
             contentDetails and status properties are not included
             in the response.

API response:

{ 
 "kind": "youtube#videoListResponse",
 "etag": "\"UCBpFjp2h75_b92t44sqraUcyu0/sDAlsG9NGKfr6v5AlPZKSEZdtqA\"",
 "videos": [
  {
   "id": "7lCDEYXw3mM",
   "kind": "youtube#video",
   "etag": "\"UCBpFjp2h75_b92t44sqraUcyu0/iYynQR8AtacsFUwWmrVaw4Smb_Q\"",
   "snippet": { 
    "publishedAt": "2012-06-20T22:45:24.000Z",
    "channelId": "UC_x5XG1OV2P6uZZ5FSM9Ttw",
    "title": "Google I/O 101: Q&A On Using Google APIs",
    "description": "Antonio Fuentes speaks to us and takes questions on working with Google APIs and OAuth 2.0.",
    "thumbnails": {
     "default": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/default.jpg"
     },
     "medium": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/mqdefault.jpg"
     },
     "high": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/hqdefault.jpg"
     }
    },
    "categoryId": "28"
   },
   "statistics": {
    "viewCount": "3057",
    "likeCount": "25",
    "dislikeCount": "0",
    "favoriteCount": "17",
    "commentCount": "12"
   }
  }
 ]
}

URL: https://www.googleapis.com/youtube/v3/videos?id=7lCDEYXw3mM&key=YOUR_API_KEY
     &part=snippet,statistics&fields=items(id,snippet,statistics)

Description: This example adds the fields parameter to remove all
             kind and etag properties from the API response.

API response:

{ 
 "videos": [
  {
   "id": "7lCDEYXw3mM",
   "snippet": { 
    "publishedAt": "2012-06-20T22:45:24.000Z",
    "channelId": "UC_x5XG1OV2P6uZZ5FSM9Ttw",
    "title": "Google I/O 101: Q&A On Using Google APIs",
    "description": "Antonio Fuentes speaks to us and takes questions on working with Google APIs and OAuth 2.0.",
    "thumbnails": {
     "default": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/default.jpg"
     },
     "medium": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/mqdefault.jpg"
     },
     "high": {
      "url": "https://i.ytimg.com/vi/7lCDEYXw3mM/hqdefault.jpg"
     }
    },
    "categoryId": "28"
   },
   "statistics": {
    "viewCount": "3057",
    "likeCount": "25",
    "dislikeCount": "0",
    "favoriteCount": "17",
    "commentCount": "12"
   }
  }
 ]
}

URL: https://www.googleapis.com/youtube/v3/videos?id=7lCDEYXw3mM&key=YOUR_API_KEY
     &fields=items(id,snippet(channelId,title,categoryId),statistics)&part=snippet,statistics

Description: This example modifies the fields parameter from example 3
             so that in the API response, each video resource's snippet
             object only includes the channelId, title,
             and categoryId properties.

API response:

{ 
 "videos": [
  {
   "id": "7lCDEYXw3mM",
   "snippet": { 
    "channelId": "UC_x5XG1OV2P6uZZ5FSM9Ttw",
    "title": "Google I/O 101: Q&A On Using Google APIs",
    "categoryId": "28"
   },
   "statistics": {
    "viewCount": "3057",
    "likeCount": "25",
    "dislikeCount": "0",
    "favoriteCount": "17",
    "commentCount": "12"
   }
  }
 ]
}

Optimizing performance

Accept-Encoding: gzip
User-Agent: my program (gzip)