Visualization libraries · University of Washington Interactive Data Lab

Vega-Lite

JSON-based grammar for concise, declarative charts, compiled to Vega, used to power Python's Altair and Observable notebooks.

Vega-Lite is a declarative, JSON-based grammar of graphics: a chart is described as a mapping of data fields to visual encodings (position, color, size, shape) rather than drawn imperatively. It compiles those specifications down to full Vega specs, which handle the actual rendering, interaction, and layout. This gives Vega-Lite a concise syntax — a bar chart or scatterplot is a few lines of JSON — while still supporting layering, faceting, and interactive selections like brushing and linked filtering. It runs in the browser via JavaScript and is the engine behind Python's Altair library, making it usable directly from notebooks without writing JSON by hand. Vega-Lite trades some of raw D3's flexibility for speed of authoring and easier reasoning about chart structure.

At a glance

Vendor University of Washington Interactive Data Lab
Pricing model Open source + paid options
Free tier Yes
Deployment Self-hosted
Open source Yes (BSD-3-Clause)
Best for Developers and data scientists who want concise, declarative chart specs rather than imperative drawing code.

Pricing

Free, open-source project maintained by the UW Interactive Data Lab with no pricing page.

Pricing has not been verified yet — see the vendor's site.

Features

  • Declarative JSON grammar of graphics
  • Compiles to full Vega specifications
  • Layered and faceted chart composition
  • Interactive selections (brushing, filtering, panning)
  • Compact specs suitable for notebooks
  • Renders via SVG or Canvas

Integrations

Profile last reviewed September 21, 2026

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