# vega/vega

A visualization grammar.

Repository: https://github.com/vega/vega
Canonical: https://ross.abutalabs.com/products/vega
Homepage: https://vega.github.io/vega
Language: JavaScript
License: BSD-3-Clause
License Family: permissive
Topics: visualization-grammar, visualization, canvas, svg, vega, d3
Last push: 2026-08-22T20:30:39+00:00

## Health v2 (maintenance only)
Score: 99/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 98, longevity 100
- inputs: {"age_days": 4959, "days_push": 11, "days_rel": 19, "gap_med": 13.0, "n_releases_24m": 11}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 11977, forks 1577 (observed 2026-08-28T04:10:50.588687+00:00)

## What it is
Vega is a declarative visualization grammar that lets you describe interactive data visualizations in JSON format. Its JavaScript runtime parses specifications to render web-based views using HTML5 Canvas or SVG, including scales, axes, legends, map projections, and reactive interaction signals.

## Use cases
- create interactive charts from JSON specifications
- build custom data visualizations in the browser
- render static chart images from a declarative spec
- define reactive visualizations that respond to input events
- generate visualizations programmatically as a foundation for charting tools
- share and reuse visualization designs as portable JSON

## When to choose
- you need fine-grained control over every visual and interactive detail of a chart
- you want a portable JSON format for generating or sharing visualizations
- you're building higher-level visualization APIs or tools on top of a grammar
- you need Canvas or SVG rendering with reactive signals in the browser

## When to avoid
- you just need common statistical charts quickly - use Vega-Lite or Altair instead
- you want a simple imperative charting API rather than a declarative grammar
- you need server-side rendering outside JavaScript environments without extra tooling

## Facets
- artifact type: library
- maturity: stable
- function: data-visualization, charts, templating
- domain: data-visualization, web-development, frontend
- platform: browser
- tags: visualization-grammar, declarative-visualization, svg, canvas, d3, interactive-visualization, json-specification, nodejs, javascript

## Member repositories
- vega/vega (main) score 99

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:50.588687+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:15:01.779895+00:00, confidence not recorded.
  - readme: https://github.com/vega/vega (fetched 2026-08-28T04:10:50.588687+00:00, sha 55c303d336b5)
  - homepage: https://vega.github.io/vega (fetched 2026-08-29T08:13:06.446615+00:00, sha 39c1d2dd732f)
- Data as of 2026-08-30T08:39:29.467469+00:00.