Every chart worth knowing.

Bar Chart

Compare quantities across categories using vertical bars positioned on a common baseline.

Bullet Chart

A compact bar with reference markers that replaces gauges and meters for KPI dashboards.

Butterfly Chart

Back-to-back horizontal bars for any two-sided comparison, with the category labels in the center gutter.

Diverging Bar Chart

Bars extend left and right from a central baseline to show positive and negative values.

Dot Plot

Positions dots along a quantitative axis to compare values with minimal ink and maximum clarity.

Dumbbell Chart

Two dots connected by a line showing the gap between two values per category.

Grouped Bar Chart

Multiple bars per category placed side by side for direct comparison across groups.

Horizontal Bar Chart

Bars drawn horizontally, ideal when category labels are long or numerous.

Lollipop Chart

A dot on a thin stem, a lighter alternative to bar charts that reduces visual clutter.

Paired Bar Chart

Two bars per category placed adjacent for direct pairwise comparison.

Pictogram Chart

Uses repeated icons to represent quantities. Engaging but imprecise.

Population Pyramid

Back-to-back horizontal bars showing age distribution by gender.

Radial Bar Chart

Bars wrapped around a circular axis. Visually striking but less precise than linear bars.

Range Plot

Horizontal min-max range bars per category — Tufte's range-frame style for compact range comparisons.

Distribution

How is the data spread?

11 entries

Bee Swarm Plot

Uses a d3-force simulation to displace overlapping points outward from the value axis, so every observation stays visible and the swarm width encodes local density. Unlike a strip/jitter plot (random scatter) it is deterministic and density-aware; unlike a violin plot (kernel estimate) it preserves exact values.

Box Plot

Shows distribution through quartiles, median, whiskers, and outliers.

Density Plot

Smooth continuous estimate of a distribution using kernel density estimation.

ECDF

Empirical cumulative distribution function, a step function showing the proportion of data at or below each value.

Error Bar Chart

Bars annotated with ± error markers — the scientific publication standard for mean ± SD or 95% CI comparisons.

Histogram

Shows frequency distribution of a numeric variable by grouping values into bins.

Q-Q Plot

Compares a distribution against a theoretical distribution (e.g. normal) point by point.

Ridgeline Plot

Stacked density plots for comparing many distributions, also called Joy Plot.

Stem-and-Leaf Plot

Hybrid of table and histogram that preserves individual data values while showing distribution shape.

Strip / Jitter Plot

Individual data points with random horizontal jitter to prevent overlap.

Violin Plot

Combines box plot with kernel density to show full distribution shape.

Composition

What makes up the whole?

11 entries

100% Stacked Bar

Stacked bar normalized to 100% that compares proportions, not totals.

Donut Chart

A ring chart showing part-to-whole with a hollow center for summary text.

Marimekko Chart

A mosaic of variable-width columns that encodes two dimensions of part-to-whole.

Nightingale Chart

Polar area chart with wedges of equal angle but varying radius, a polar histogram.

Pie Chart

A circle divided into slices. Familiar but less precise than bar charts.

Polar Area Chart

Smooth continuous area plotted in polar coordinates. Ideal for cyclic data (24-hour cycles, compass directions, monthly seasonality).

Proportional Symbol

Symbols (circles, squares) sized by value, placed on a category axis or map.

Stacked Area Chart

Layered areas showing how parts of a whole change over time.

Stacked Bar Chart

Bars divided into colored segments showing composition per category.

Treemap

Nested rectangles sized by value, showing hierarchical part-to-whole for many categories.

Waffle Chart

A 10x10 grid of squares, each representing 1%. Intuitive for percentages.

Relationship

How are variables related?

11 entries

2D Contour Plot

Contour lines showing density of points in 2D space, like a topographic map.

Bubble Chart

Scatter plot with a third variable encoded as circle size — typically two correlated metrics on x/y plus a magnitude on bubble area.

Connected Scatter Plot

Scatter plot with points connected by lines, showing trajectory through two dimensions.

Correlogram

Symmetric grid of every variable pair's correlation coefficient, with circle size encoding magnitude and color encoding sign — diagonal blocks of strongly-correlated variables jump out instantly.

Heatmap

Color-coded matrix revealing patterns across two categorical dimensions.

Hexbin Plot

Aggregates dense scatter points into hexagonal bins colored by count.

Mosaic Plot

Categorical × categorical contingency table where both row heights and column widths within each row are proportional to joint frequency.

Pair Plot / Scatter Matrix

n×n grid of scatter plots for every variable pair, with the diagonal showing each variable's distribution — letting you spot non-linear relationships, clusters, and outliers across all pairs at once before fitting any model.

Quadrant Chart

2×2 strategic matrix that plots items by two scores and divides the plane into four quadrants — the BCG / Eisenhower / impact-effort visual.

Regression Plot

Scatter plot with a fitted trend line showing the linear or polynomial relationship between two variables.

Scatter Plot

Plots two numeric variables as points, revealing correlations, clusters, and outliers.

Time Series

How does it change over time?

11 entries

Area Chart

Filled area under a line that emphasizes volume and magnitude over time.

Calendar Heatmap

Daily values mapped to a calendar grid, revealing day-of-week and seasonal patterns.

Candlestick / OHLC

Shows open, high, low, close for financial data. Each candle is one time period.

Event Timeline

Discrete events as point markers on a single time axis, optionally grouped into lanes — distinct from a Gantt (no bar lengths / durations) and from sparkline-with-annotations (events are the primary mark, not the overlay).

Fan Chart

Line chart with expanding confidence bands that shows forecast uncertainty.

Gantt Chart

Horizontal bars on a time axis showing task durations, dependencies, and overlap.

Horizon Chart

Layered, folded area chart that shows many time series in minimal vertical space.

Index Chart

Line chart rebased so every series starts at 100. Reads as 'normalized growth from baseline,' making relative change comparable across series of very different absolute magnitudes.

Line Chart

Connects data points with lines to show trends over time. The workhorse of time-series visualization.

Sparkline

Tiny inline chart with no axes that shows trend in the context of text or tables.

Step Chart

Line chart with horizontal steps between points. No interpolation between values.

Ranking

What is the order?

06 entries

Alluvial Chart

Visualizes categorical flows across multiple stages using curved bands whose width encodes quantity, revealing how groups merge and split.

Bar Chart Race

An animated horizontal bar chart where bars re-sort over time to show how rankings change, creating a dynamic 'race' effect.

Bump Chart

Displays how the ranking of items changes over time using curved or straight lines that shift vertically to reflect position changes.

Ordered Dot Plot

Plots items as dots along a quantitative axis, sorted by value, making it easy to read rank order and spot gaps between items.

Parallel Coordinates

Plots multivariate data with one vertical axis per variable, connecting each observation's values with a polyline across all axes.

Slope Chart

Connects paired values across two points in time (or two categories) with lines, emphasizing direction and steepness of change.

Flow

How does it move between stages?

07 entries

Arc Diagram

Places nodes along a line and draws arcs between connected pairs, revealing clusters and bridges in network data.

Chord Diagram

Displays flows between entities arranged in a circle, with arc widths encoding volume of bidirectional relationships.

Flow Map

Overlays directional flow lines on a geographic map, showing movement of goods, people, or information between locations.

Funnel Chart

Shows progressive reduction through sequential stages, with bar widths encoding volume at each step.

Network Graph

Displays entities as nodes and their relationships as edges in a force-directed or fixed 2D layout.

Node-Link Tree

Hierarchy drawn as explicit parent→child link lines (top-down or radial), where each step in the chain is independently traceable — distinct from a treemap or sunburst, which encode hierarchy via nested area without showing the path that connects nodes.

Sankey Diagram

Shows flows between nodes using bands whose width encodes quantity, revealing how resources move through a system.

Part-to-Whole

What fraction is each piece?

07 entries

Circle Packing

Nests circles within circles to represent hierarchical data, with area encoding value at each level.

Icicle Chart

A rectangular, space-filling hierarchy chart where nested rectangles hang vertically to show depth and proportion.

Nested Donut

Stacks concentric donut rings to show hierarchical composition, with each ring representing a level of the hierarchy.

Parliament Chart

Arranges dots in a hemicycle to show seat distributions in a legislative body, with color encoding party affiliation.

Sunburst Chart

A radial treemap where concentric rings represent hierarchy levels and arc angles encode proportions at each depth.

Unit Chart

Represents each data point as an individual icon or shape, making counts tangible and part-to-whole ratios intuitive.

Voronoi Treemap

Partitions space into irregular polygons whose areas represent values, offering an organic alternative to rectangular treemaps.

Geospatial

Where is it?

08 entries

Bubble Map

Circles sized by value placed at geographic locations.

Cartogram

Distorts region sizes to reflect a variable. Area represents data, not geography.

Choropleth Map

Regions colored by value, the most common thematic map type.

Connection Map

Lines connecting locations, showing routes, flights, or relationships between places.

Dot Map

One dot per occurrence, showing density and distribution of point events.

Hexagonal Grid Map

Equal-sized hexagons represent regions, eliminating area bias.

Spike Map

Vertical spikes at locations sized by value, avoiding area distortion of bubble maps.

Tile Grid Map

Each region is a square tile in a grid with equal visual weight and no geographic distortion.

Specialized

Domain-specific visualizations

18 entries

Bullet Sparkline

Compact inline bullet chart for tables and dense dashboards.

Combo Chart

Overlays bars and lines with dual Y-axes to show volume and rate together.

Data Table

A structured tabular display with sortable columns, ideal when users need exact values rather than visual patterns.

Dendrogram

Tree diagram showing hierarchical clustering - branches merge at similarity thresholds.

Gauge Chart

Semicircular meter showing a single value against a scale, like a car speedometer.

Heat Table

Data table with cells colored by value - spreadsheet meets heatmap.

Infographic Stat Block

Bold, large-format number cards arranged in a grid, designed for presentations and infographic-style layouts.

Isoline / Contour Chart

Lines connecting equal values - like elevation contours on a topographic map.

KPI Card

A bold single-metric display card showing a headline number with optional comparison to a previous period.

Matrix Diagram

Grid showing relationships between two sets of items - filled cells indicate connections.

Metric Comparison Card

Side-by-side display of multiple KPIs with current vs previous values and change indicators.

Progress Bar / Tracker

Horizontal bars showing progress toward defined targets, ideal for goal tracking dashboards.

Radar / Spider Chart

Variables plotted on radial axes from a center point, showing multivariate profiles.

Small Multiples

Same chart repeated for each subset, enabling comparison across a grid of panels.

Streamgraph

Organic flowing layers around a central baseline that show volume changes across categories over time.

Venn / Euler Diagram

Overlapping circles showing set intersections and relationships.

Waterfall Chart

Shows how an initial value is affected by sequential positive and negative changes.