Simple humidity chart card
Who it’s for
Building managers, HVAC engineers, and environmental monitoring teams ask “how has humidity 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 52% shows a color-coded value above a chart that reveals whether humidity has been rising toward damp conditions or falling toward dryness over the selected period.
- Large current humidity value in the center, color-coded across five bands from Very Dry to Very Humid
- Time-series chart of humidity readings over the selected time window, averaged per interval
- Shows one sensor’s data; it does not compare multiple zones or show period-over-period deltas
How to set up
Data keys
| Key | Role | Type | Description |
|---|---|---|---|
humidity | Chart series | Timeseries | Relative humidity in %; 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 Humidity, 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 |
|---|---|---|
| 0–20 | Very Dry | Red |
| 20–40 | Dry | Orange |
| 40–60 | Comfortable | Blue |
| 60–80 | Humid | Dark Blue |
| 80–100 | Very Humid | Deep Blue |
How to customize
- To use your own humidity thresholds — edit the color ranges on the Latest data key; adjust the five default bands to match your facility’s targets.
- 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 period-over-period change. Add the full humidity chart card if you need a delta percentage alongside the chart.
- A rising line drifting above 60% warns of mold risk. A falling line dropping below 30% suggests the space is getting too dry for comfort.
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