The API Widget key is a single string that defines how your widget works.
It connects the widget template, visual theme, and your data source.

You paste this key into the app to configure a widget.

An API Widget key defines:

• which template is used (for example, W12),
  
• which visual theme is applied,
  
• where the widget fetches its JSON data from.
  

Changing the key is all you need to update the widget configuration.

An API Widget key consists of several parts combined into one string.

Conceptually, it looks like this:
[ version :: template :: theme :: source :: data-endpoint ]

Each part has a specific purpose:

• version — identifies the key format version
  
• template — defines the widget layout
  
• theme — controls the visual appearance
  
• source — defines the data source type (for example, json)
  
• data-endpoint — the URL of your JSON API endpoint
  

The exact key format is handled by the app, so you don’t need to construct it manually.

🧩 API Widget Key Examples:

1) A simple W12 widget with the default dark theme:
v1::w12::dark::json::https://example.com/json-endpoint

2) The same data endpoint, using a different visual theme:
v1::w12::terminal::json::https://example.com/json-endpoint

3) A widget displaying live metrics from another endpoint:
v1::w12::dark::json::https://api.example.com/metrics

4) Using built-in demo data (demo source #1):
v1::w12::light::demo::1

The data endpoint must:

• be publicly accessible over HTTPS,
  
• return valid JSON,
  
• follow the format expected by the selected template.
  

For the W12 template, the endpoint should return a list of key–value rows.

➡️ See W12 Template for the required JSON structure.

If you need to change:

• the data source,
  
• the theme,
  
• or the template,
  

simply update the API Widget key in the app.
The widget will refresh automatically based on system conditions.

If a widget doesn’t display data, check that:

• the endpoint URL is correct and reachable,
  
• the endpoint returns valid JSON,
  
• the data format matches the selected template,
  
• the key has no extra spaces or missing parts.
  

➡️ See Troubleshooting for detailed solutions.

To learn more about data formatting and styling, continue with:
➡️ W12 Template — supported fields, colors, and limits.