Simple air quality index chart card with background
Who it’s for
Dashboard authors monitoring outdoor air quality stations or smart city sensors ask “how has the AQI changed over time?” They want a clean trend view with a recognizable background for dedicated displays or reception screens.
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, displayed over the preset background image.
- 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
- Decorative background image bundled with the widget, with a white overlay that keeps the text readable
- 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 swap the background image — open the widget settings and set Background to a different image or switch to a solid color.
- To adjust how much the background shows through — change the Overlay opacity; lower values reveal more of the image, higher values push it further back.
- 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.
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.
- If the background image reduces contrast, raise the Overlay opacity to keep the text readable from a distance.
- 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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