# showdownjs/showdown

A bidirectional Markdown to HTML to Markdown converter written in Javascript

Repository: https://github.com/showdownjs/showdown
Canonical: https://ross.abutalabs.com/products/showdown
Language: JavaScript
License: MIT
License Family: permissive
Topics: showdown, javascript, markdown, markdown-parser, markdown-flavors, gfm, html, converter, html-converter
Last push: 2026-08-25T09:39:56+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 8, longevity 100
- inputs: {"age_days": 6502, "days_push": 8, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 14869, forks 1566 (observed 2026-08-28T04:11:08.830992+00:00)

## What it is
Showdown is a bidirectional Markdown to HTML (and HTML to Markdown) converter library written in JavaScript. It runs both client-side in the browser and server-side in Node.js, supporting Markdown flavors like GFM.

## Use cases
- convert markdown to html in the browser
- render user-submitted markdown comments as html
- convert html back to markdown
- parse markdown files in node.js
- add a markdown editor preview to a web app
- support gfm extensions like tables and task lists

## When to choose
- you need a pure-JavaScript markdown converter with no native dependencies
- you need both markdown-to-html and html-to-markdown conversion
- you need the same parser to work in the browser and on the server
- you need GFM flavor support or custom extensions

## When to avoid
- you need extremely high-performance parsing of huge documents
- you need full CommonMark spec compliance with strict conformance
- you are rendering untrusted markdown and need built-in sanitization (pair it with a sanitizer)
- your stack is not JavaScript

## Facets
- artifact type: library
- maturity: stable
- function: parser, markdown, serialization
- domain: web-development, frontend, developer-tools, documentation
- platform: browser, cross-platform
- tags: markdown-to-html, html-to-markdown, gfm, bidirectional-converter, text-processing, nodejs, javascript

## Member repositories
- showdownjs/showdown (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:08.830992+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 2026-08-29T17:07:01.420217+00:00, confidence not recorded.
  - readme: https://github.com/showdownjs/showdown (fetched 2026-08-28T04:11:08.830992+00:00, sha 2ea7600c7da0)
  - registry_npm: https://registry.npmjs.org/showdown (fetched 2026-08-29T08:05:18.149519+00:00, sha be675a702928)
- Data as of 2026-08-30T08:39:29.467469+00:00.