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Simple humidity chart card with background

  • Widget
  • 21 installs
  • v1.0.0
  • Jun 15, 2026
  • MIT license
  • v4.2+

Displays historical humidity values as a simplified chart with background. Optionally may display the corresponding latest humidity value.

Widget Type
  • Timeseries
Category
  • Charts & Graphs
Use Cases
  • Environment Monitoring
  • Smart City
  • Smart Building
  • Smart Farming

Who it’s for

Building managers, HVAC engineers, and environmental monitoring teams ask “how has humidity changed over time?” They want a clean trend view with a recognizable background for dedicated building management displays or reception screens.

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, displayed over the preset background image.

  • 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
  • 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 zones or show period-over-period deltas

How to set up

Data keys

KeyRoleTypeDescription
humidityChart seriesTimeseriesRelative humidity in %; drives the chart. The Latest value overlay is automatically derived from this same key
LatestLatest valueTimeseriesThe 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 (%)LevelColor
0–20Very DryRed
20–40DryOrange
40–60ComfortableBlue
60–80HumidDark Blue
80–100Very HumidDeep Blue

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 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 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 period-over-period change. Add the full humidity 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.

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