Common Information ​

The launch parameters are the list of parameters that is passed by the native Telegram application to the Mini App. It helps the developer to find out the characteristics of the Telegram application, the current device, get basic information about the user and much more.

Transmission Method ​

It's easy to guess, but in a web environment, one of the simplest and most instantaneous ways to transfer data in a local environment is to specify them in the address bar of the application. Thus, both the called server and the downloaded application will have some pre-known data. Actually, Telegram Mini Apps technology uses the same algorithm.

The native Telegram application transmits a list of these parameters in the dynamic part of the URL (in the hash, #). Accordingly, in order to access these parameters, it is necessary to access the window.location.hash property from the JavaScript code.

Extraction ​

It is important to remember that hash is a string property, while Telegram transmits a whole list of properties, after which the question arises about formatting and processing this list. In fact, everything is quite simple.

The native Telegram application passes the list of launch parameters as query-parameters and saves the resulting string in window.location.hash. For this reason, in order to extract the launch parameters, it is enough to perform the following operation:

const hash = window.location.hash.slice(1);
console.log(hash); // tgWebAppData=...&tgWebAppVersion=6.2&...

const params = new URLSearchParams(hash);
console.log(params.get('tgWebAppVersion')); // "6.2"

const hash = window.location.hash.slice(1);
console.log(hash); // tgWebAppData=...&tgWebAppVersion=6.2&...

const params = new URLSearchParams(hash);
console.log(params.get('tgWebAppVersion')); // "6.2"

Parameters List ​

tgWebAppVersion ​

The current Telegram Mini Apps version used by the native application. This parameter is important to use, for example, before calling the Telegram Mini Apps methods to make sure, they are supported.

tgWebAppData ​

Contains data describing the current user, data sign, and also some useful values. To learn more, visit the Init Data page.

This parameter is passed as query parameters, so in order to get a more user-friendly value, a developer need to use the URLSearchParams constructor:

const initData = new URLSearchParams(params.get('tgWebAppData'));

// ['user', '{"id":279058397,"first_name":"Vladislav", ... }']
// ['chat_instance', '8428209589180549439']
// ['chat_type', 'sender']
// ['auth_date', '1698272211']
// ['hash', 'ddc15fc7419ae9cb9a597b98efee42ea0']

const initData = new URLSearchParams(params.get('tgWebAppData'));

// ['user', '{"id":279058397,"first_name":"Vladislav", ... }']
// ['chat_instance', '8428209589180549439']
// ['chat_type', 'sender']
// ['auth_date', '1698272211']
// ['hash', 'ddc15fc7419ae9cb9a597b98efee42ea0']

tgWebAppPlatform ​

Telegram application identifier. It can be used as a factor determining the visual style of the application, for example, when, depending on the device, the developer needs to display components that are different visually.

tgWebAppThemeParams ​

Parameters of the native Telegram application theme. This parameter can be used to style the application even at the moment of rendering the loader.

The value of this parameter is a JSON object converted to the string. To get a more user-friendly value, it is enough to use the JSON.parse method.

const theme = {
  bg_color: '#212121',
  text_color: '#ffffff',
  hint_color: '#aaaaaa',
  link_color: '#8774e1',
  button_color: '#8774e1',
  button_text_color: '#ffffff',
  secondary_bg_color: '#0f0f0f',
};

const theme = {
  bg_color: '#212121',
  text_color: '#ffffff',
  hint_color: '#aaaaaa',
  link_color: '#8774e1',
  button_color: '#8774e1',
  button_text_color: '#ffffff',
  secondary_bg_color: '#0f0f0f',
};

tgWebAppShowSettings ​

Parameter used only by Telegram SDK to show the Settings Button on startup. It has no other meaning to external developers.

tgWebAppBotInline ​

This parameter is being added in case the current application is launched in inline mode. This allows calling such Telegram Mini Apps method as web_app_switch_inline_query.

tgWebAppStartParam ​

This parameter is being included in case, bot link contains such query parameter as startattach, or Direct Link contains the startapp query parameter.

Here are the examples:

• https://t.me/botusername?startattach=PARAM
• https://t.me/botusername/appname?startapp=PARAM

In both of these cases, tgWebAppStartParam will be set to "PARAM".