Gauge Chart
Also called: Speedometer chart, Dial chart
A gauge chart shows a single value on a semicircular scale from a minimum to a maximum, usually with a marker for the target, like a speedometer.
What a gauge shows
A gauge has four parts:
- The scale. A min and max, often 0–100%.
- The value. The filled part of the arc, plus the number in the middle.
- The target. A tick mark on the arc, so readers can see the gap at a glance.
- The label. What’s being measured, such as Capacity utilisation.
Some gauges add coloured bands (red / amber / green) to show zones. Use them only if the thresholds are agreed, otherwise the colours mislead.
Where gauges go on a dashboard
Gauges take up a lot of space for one number, so use them sparingly. One or two per page, usually in the top row next to KPI cards, for the metrics that are about hitting a target. A row of six gauges is hard to compare. Use a bar chart with target lines instead.
Best practices
- Always show the target. A gauge with no target is just a slower KPI card.
- Start the scale at a meaningful zero. A 60–100% scale exaggerates small changes.
- Label the number, not just the arc. People read the digits first.
Mocking up a gauge
Gauges often get asked for by name (“can we have a speedometer?”). Put one in the mockup next to a KPI card showing the same metric, and let stakeholders pick. It usually settles the debate quickly.
