Thresholds turn a key (or dial bar) into a warning light. Set a Warn at and/or Critical at value, and the plugin colors the reading the moment its live value crosses the limit: amber for warn, red for critical.
Both fields are optional and independent: set one, the other, or neither. A key with no thresholds just shows its themed value.
The two fields
| Field | Effect on a key | Effect on a dial |
|---|---|---|
| Warn at | Whole face flips to amber field / black text | Range bar fill turns amber |
| Critical at | Whole face flips to red field / white text | Range bar fill turns red |
| Direction (Alert when value drops below thresholds) | Flips the comparison so a low value is the alarm | Same |
On a key the alert takes over the entire face; this is deliberate, aviation-style master caution/warning that reads across a whole wall of keys. On a Stream Deck + dial the touchscreen slot is too small for a full flip, so only the range bar’s fill changes color; the label, value and range text stay themed. See Sensor Dial for the rest of the dial.
How the comparison works
Two rules matter, and both are easy to get wrong:
1. Thresholds are in the displayed unit. The value compared against your thresholds is the live (current) reading in whatever unit the key shows, after the °C→°F conversion, not before. So if you tick Show temperatures in °F, a Warn at of 100 fires on a 40 °C core (which displays as 104 °F). Leave °F off and the same sensor is compared in °C. Match your numbers to the unit on the face.
Note: Alert color always tracks the live value, even when the key is showing MIN / MAX / AVG (press cycles the stat mode). Pressing a key to look at its max won’t turn the alert off if the current value is still over the limit, and won’t turn it on just because the historical max was.
2. The trigger is “at or past” the limit. Crossing means reaching the value, not exceeding it:
- Normal direction (higher is worse): alerts when
value ≥ threshold. - Below direction (lower is worse): alerts when
value ≤ threshold.
Critical is checked before warn, so once a reading is past both limits it shows critical.
Decimal commas are accepted
Both fields accept a period or a comma as the decimal separator, so 70.5 and 70,5 both mean seventy-and-a-half. Blank means “no threshold”. Anything that isn’t a number is ignored (treated as no threshold).
Direction: alert when high vs. alert when low
By default higher is worse, the right setting for temperatures, power draw, and usage. Tick Alert when value drops below thresholds for readings where low is the problem:
- Fan RPM: a stalled or dying fan reads low.
- Free disk space: you want to know when it drops under a floor.
- Battery %, available memory, and similar “headroom” readings.
With the box ticked, your Warn at / Critical at values become floors: the alert fires when the reading falls to or below them.
Colors are global and colorblind-safe
The warn and critical palettes are never themed. Amber-warn and red-crit look identical on Void, Paper, Ember, or any other theme: an alert must be unmistakable regardless of the surrounding look. The two states are separated by luminance as well as hue (bright amber field vs. deep red field), so they stay distinguishable under any color-vision deficiency. Type accents don’t apply to an alerting key either; the alert owns the whole palette.
Worked examples
CPU temperature: warn 80, crit 90
A typical desktop-CPU key in °C:
- Warn at
80 - Critical at
90 - Direction: leave unticked (higher is worse)
Idle and under load the key stays themed. At 80 °C it goes amber; at 90 °C it goes red. If you’d rather read the face in Fahrenheit, tick Show temperatures in °F and enter the thresholds in °F (e.g. 176 / 194); the numbers must match the displayed unit.
Fan RPM: alert when it drops
A fan you want to catch stalling:
- Warn at
500 - Critical at
300 - Direction: ticked (alert when below)
Above 500 RPM the key is normal; at 500 or under it warns; at 300 or under it goes critical (0 RPM = a stopped fan = red).
Free disk space: alert on a low floor
Free space in GB, so you notice before a drive fills:
- Warn at
50 - Critical at
20 - Direction: ticked (alert when below)
Drops to 50 GB → amber; drops to 20 GB → red.
Tip: When you use the below direction, set Critical at lower than Warn at (crit is the worse, deeper floor). Because critical is evaluated first, an inverted pair (e.g. warn 300, crit 500 with below on) makes the reading go straight to critical without ever showing warn.
Where thresholds live
The Warn at, Critical at and Direction controls are on both the Sensor Reading (key) and Sensor Dial property inspectors, just below the display options. They’re per-key / per-dial (each reading gets its own limits) and they persist with the rest of that button’s settings.