This entry is part of the Chart Index, the reference library for the Chart Design Field Guide.
The bullet chart is Stephen Few's answer to the gauge. Where a gauge wastes a half-circle of space to show one number against a target, a bullet does the same job in a thin horizontal strip — one row in a table cell, twenty rows in the space of a single dashboard tile. It is a chart designed for KPI displays, status boards, and any situation where the question is how close is the actual to the target, given a notion of normal?
The form is austere and information-dense. A short horizontal bar shows the actual value. A thin marker shows the target. A shaded band shows the qualitative range — poor, satisfactory, good. The eye reads all three at a glance.
What it is
A bullet chart consists of three superimposed elements: a quantitative range bar (background) divided into qualitative bands; a measure bar (foreground) encoding the actual value; and a comparative marker (a short perpendicular tick) encoding the target. The whole composition occupies a single horizontal strip, typically 20–24 pixels tall.
Six metrics, each on its own row. The eye scans down the actual bars, picks up the target tick, and reads the qualitative band in the background. Metrics that are below target but within good range — and metrics that are above target but in only the satisfactory band — both stand out without effort.
When to use it
Bullet charts are the right choice when:
- You have multiple KPIs with targets that need to be tracked.
- The reader's question is "are we on target, and how close to the band edges are we?"
- You need a dense display — bullet charts pack 6–20 metrics into the space of one panel.
- Each metric has a qualitative interpretation of value — good, satisfactory, poor — that can be encoded as background bands.
- The form is operational or executive, not exploratory.
When not to use it
- Single-metric display. A standalone bullet is fine but unremarkable; the form's value is in dense multi-metric arrays.
- Distributions. A bullet shows a single value against bands; it does not show spread, percentiles, or variability over time. Use a box plot or sparkline.
- Categorical comparison without targets. Without a target marker and qualitative bands, a bullet is just a horizontal bar. Use a regular bar chart.
- Audiences unfamiliar with the form. Bullets read instantly once you know the encoding; without orientation, the bands can confuse.
Design principles
Define the qualitative bands carefully
The bands — typically three shades of the same hue, from lightest (poor) to darkest (good), or three categorical greys — encode the operational meaning of the value. Above 80% of target is good, 60–80% is satisfactory, below 60% is poor. These thresholds are domain decisions, not arbitrary tweaks. Document them.
Use a single colour family for the bands
Bands should never compete with the data. Three shades of cream-to-grey, or three shades of a single hue with low saturation, sit behind the measure bar without distraction. Saturated traffic-light colours (red/amber/green) draw attention to themselves and away from the value.
Make the measure bar bold and dark
The actual value is the headline. The measure bar should be the darkest, most saturated element. Few's specification: a dark grey or near-black bar that visually dominates the band background.
Make the target marker thin and central
A short perpendicular line crossing the measure bar at the target position. Three to four pixels wide; height slightly taller than the bar so it is visible whether the bar reaches the target or not.
Align bullets in a column
In a multi-metric display, every bullet should share the same horizontal scale or be normalised (e.g., 0–120% of target). The eye reads bullets in a column the way it reads numbers in a column — through alignment.
Pair with the metric label and value
A bullet chart is rarely its complete self. Beside each strip: the metric name (left), the actual value as a number (right), and optionally a delta vs. target as a percentage. The chart and the number together form one row.
Resist the urge to add colour
Few's traffic-light prohibition stems from real research. Red bad, green good is intuitive but introduces colour as a categorical dimension competing with the existing length encoding. A single hue for the data, neutral greys for the bands.
Anatomy
A bullet chart dashboard is a column of single-strip displays, every strip aligned to a shared scale, every strip carrying three encodings in one row. The form scales from one metric to dozens with linear visual cost.
Related types
- Bar chart — what a bullet becomes without the bands and target. Use when the comparison is to other categories, not a target.
- Gauge — the form bullet replaces. Mostly chartjunk; covered in a separate entry for completeness.
- Sparkline — for trend over time rather than position-against-target. Often paired with bullets in dashboards.
- Slope chart — for actual-vs-target as two points on a line. Different visual but adjacent question.
- Progress bar — a simpler form: actual against 100%. No bands, no target marker.
Reading list
- Few, S. (2006). Information Dashboard Design. The original specification of the bullet chart.
- Few, S. (2010). Bullet Graph Design Specification. The downloadable definitive guide.
- Tufte, E. (1990). Envisioning Information. On small-multiple displays and information density.