Simple air quality index chart card
Who it’s for
Dashboard authors monitoring outdoor air quality stations or smart city sensors ask “how has the AQI changed over time, without the clutter of delta comparisons?” They want to see the current reading and a trend line in one card, nothing more.
What it does
A sensor currently reading 85 AQI shows a color-coded value above a chart that reveals whether air quality has been rising or falling over the selected period.
- Large current AQI value in the center, color-coded across six severity bands from Good to Hazardous
- Time-series chart of AQI readings over the selected time window, averaged per interval
- Shows one sensor’s data; it does not compare multiple stations or show period-over-period deltas
How to set up
Data keys
| Key | Role | Type | Description |
|---|---|---|---|
air | Chart series | Timeseries | Numeric AQI reading; drives the chart. The Latest value overlay is automatically derived from this same key |
| Latest | Latest value | Timeseries | The headline figure above the chart. Its own color ranges are where the band colors are edited |
The widget ships with a simulated function datasource key labeled Air Quality Index, so it draws random values until you point the datasource at a device and rename the key.
To point it at your own device: open the dashboard in edit mode, open the widget’s Datasources, pick the entity or entity alias, and replace the function key with the key your device reports.
If the key has never reported for the selected time window, the chart is empty and the value overlay shows no data.
Value ranges
| Range | Level | Color |
|---|---|---|
| 0–50 | Good | Green |
| 50–100 | Moderate | Orange |
| 100–150 | Unhealthy (sensitive) | Orange |
| 150–200 | Unhealthy | Red |
| 200–300 | Very Unhealthy | Purple |
| 300+ | Hazardous | Maroon |
How to customize
- To use your own AQI color bands — edit the color ranges on the Latest data key; adjust the six default levels to match your monitoring thresholds.
- To hide or show the chart — toggle Show chart in the widget settings.
- To change the chart line color — set Chart color.
- To show min, max, or total in the legend instead of avg — edit the Legend settings.
- To hide the entity name subtitle or the timestamp — turn off Show subtitle or Show date.
- To match your dashboard’s fonts — set the font options under each data key’s appearance settings.
Tips
- Use this card when the trend shape matters more than the exact change. Add the full chart card if you need a delta percentage alongside the chart.
- The aggregation interval controls chart granularity. For a daily view, an hourly interval makes trends visible without too many data points.
- The default upper range starts at 300 with no upper limit. The card colors the value correctly even when a reading goes above 500.
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