sparkline

A sparkline is a small, simple chart that is embedded inline with text or within compact tabular layouts to show a trend or pattern in data. The term was popularized by Edward R. Tufte as a way to present the essence of a data series without the clutter of a full-sized chart. Sparklines prioritize compactness and immediate visual impression over precise value labeling.

Sparklines are characterized by their minimal footprint. They are typically narrow and short in height, often without axes, gridlines, or explicit data markers. The emphasis is on the overall trajectory or shape of the data across a brief time period or sequence, making them suitable for dashboards, reports, and articles where space is at a premium. They can be used alone or as part of a collection of metrics in a single row or cell.

Common types include line sparklines, which show continuous trends; bar or column sparklines, which display value magnitudes as small vertical bars; and win/loss sparklines, which summarize data as three-state indicators (up, down, and flat). Some implementations support area fills, negative values, or baseline references to provide additional context.

Design and interpretation considerations include consistent scaling across related sparklines, clear baseline cues when used, and accessible color choices. Because sparklines condense data, they are not meant for precise value interpretation but for quick assessment of patterns, such as upward trends, volatility, or abrupt changes.

Sparklines are supported in many software tools and programming libraries, including spreadsheet programs and data visualization packages. They are widely used in business dashboards, performance reports, and data journalism to convey trends efficiently within compact layouts.