showdown 正在参加 2021 年度 OSC 中国开源项目评选,请投票支持!
showdown 在 2021 年度 OSC 中国开源项目评选 中已获得 {{ projectVoteCount }} 票,请投票支持!
2021 年度 OSC 中国开源项目评选 正在火热进行中,快来投票支持你喜欢的开源项目!
2021 年度 OSC 中国开源项目评选 >>> 中场回顾
showdown 获得 2021 年度 OSC 中国开源项目评选「最佳人气项目」 !
授权协议 MIT License
开发语言 JavaScript
操作系统 跨平台
软件类型 开源软件
所属分类 应用工具
地区 不详
投 递 者 首席测试
适用人群 未知
收录时间 2021-11-10



Build Status: Linux Build Status: Windows npm version Bower version Join the chat at Greenkeeper badge Donate

Showdown is a Javascript Markdown to HTML converter, based on the original works by John Gruber. Showdown can be used client side (in the browser) or server side (with NodeJs).


Check a live Demo here


As you know, ShowdownJS is a free library and it will remain free forever. However, maintaining and improving the library costs time and money.

If you like our work and find our library useful, please donate through patreon or directly through paypal!! Your contribution will be greatly appreciated and help me continue to develop this awesome library.


ShowdownJS v 2.0 is release under the MIT version. Previous versions are release under BSD.

Who uses Showdown (or a fork)


Download tarball

You can download the latest release tarball directly from releases


bower install showdown

npm (server-side)

npm install showdown

NuGet package

PM> Install-Package showdownjs

The NuGet Packages can be found here.


You can also use one of several CDNs available:

  • jsDelivr<version tag>/dist/showdown.min.js
  • cdnjs<version tag>/showdown.min.js
  • unpkg

Note: replace <version tag> with an actual full length version you're interested in e.g. 1.9.0

Browser Compatibility

Showdown has been tested successfully with:

  • Firefox 1.5 and 2.0
  • Chrome 12.0
  • Internet Explorer 6 and 7
  • Safari 2.0.4
  • Opera 8.54 and 9.10
  • Netscape 8.1.2
  • Konqueror 3.5.4

In theory, Showdown will work in any browser that supports ECMA 262 3rd Edition (JavaScript 1.5). The converter itself might even work in things that aren't web browsers, like Acrobat. No promises.

Node compatibility

Showdown has been tested with node 0.8 and 0.10. However, it should work with previous versions, such as node 0.6.

Legacy version

If you're looking for showdown v<1.0.0, you can find it in the legacy branch.


You can check the full changelog

Extended documentation

Check our wiki pages for examples and a more in-depth documentation.

Quick Example


var showdown  = require('showdown'),
    converter = new showdown.Converter(),
    text      = '# hello, markdown!',
    html      = converter.makeHtml(text);


var converter = new showdown.Converter(),
    text      = '# hello, markdown!',
    html      = converter.makeHtml(text);


Both examples should output...

    <h1 id="hellomarkdown">hello, markdown!</h1>


You can change some of showdown's default behavior through options.

Setting options

Options can be set:


Setting a "global" option affects all instances of showdown

showdown.setOption('optionKey', 'value');


Setting a "local" option only affects the specified Converter object. Local options can be set:

  • through the constructor

    var converter = new showdown.Converter({optionKey: 'value'});
  • through the setOption() method

    var converter = new showdown.Converter();
    converter.setOption('optionKey', 'value');

Getting an option

Showdown provides 2 methods (both local and global) to retrieve previous set options.


// Global
var myOption = showdown.getOption('optionKey');

var myOption = converter.getOption('optionKey');


// Global
var showdownGlobalOptions = showdown.getOptions();

var thisConverterSpecificOptions = converter.getOptions();

Retrieve the default options

You can get showdown's default options with:

var defaultOptions = showdown.getDefaultOptions();

Valid Options

  • omitExtraWLInCodeBlocks: (boolean) [default false] Omit the trailing newline in a code block. Ex:


    <code><pre>var foo = 'bar';

    Becomes this:

    <code><pre>var foo = 'bar';</pre></code>
  • noHeaderId: (boolean) [default false] Disable the automatic generation of header ids. Setting to true overrides prefixHeaderId

  • customizedHeaderId: (boolean) [default false] Use text in curly braces as header id. (since v1.7.0) Example:

    ## Sample header {real-id}     will use real-id as id
  • ghCompatibleHeaderId: (boolean) [default false] Generate header ids compatible with github style (spaces are replaced with dashes and a bunch of non alphanumeric chars are removed) (since v1.5.5)

  • prefixHeaderId: (string/boolean) [default false] Add a prefix to the generated header ids. Passing a string will prefix that string to the header id. Setting to true will add a generic 'section' prefix.

  • rawPrefixHeaderId: (boolean) [default false] Setting this option to true will prevent showdown from modifying the prefix. This might result in malformed IDs (if, for instance, the " char is used in the prefix). Has no effect if prefixHeaderId is set to false. (since v 1.7.3)

  • rawHeaderId: (boolean) [default false] Remove only spaces, ' and " from generated header ids (including prefixes), replacing them with dashes (-). WARNING: This might result in malformed ids (since v1.7.3)

  • headerLevelStart: (integer) [default 1] Set the header starting level. For instance, setting this to 3 means that

    # foo

    will be parsed as

  • parseImgDimensions: (boolean) [default false] Enable support for setting image dimensions from within markdown syntax. Examples:

    ![foo](foo.jpg =100x80)     simple, assumes units are in px
    ![bar](bar.jpg =100x*)      sets the height to "auto"
    ![baz](baz.jpg =80%x5em)  Image with width of 80% and height of 5em
  • simplifiedAutoLink: (boolean) [default false] Turning this option on will enable automatic linking to urls. This means that:

    some text

    will be parsed as

    <p>some text <a href=""></a>
  • excludeTrailingPunctuationFromURLs: (boolean) [default false] This option excludes trailing punctuation from autolinking urls. Punctuation excluded: . ! ? ( ). Only applies if simplifiedAutoLink option is set to true.

  • literalMidWordUnderscores: (boolean) [default false] Turning this on will stop showdown from interpreting underscores in the middle of words as <em> and <strong> and instead treat them as literal underscores.


    some text with__underscores__in middle

    will be parsed as

    <p>some text with__underscores__in middle</p>
  • literalMidWordAsterisks: (boolean) [default false] Turning this on will stop showdown from interpreting asterisks in the middle of words as <em> and <strong> and instead treat them as literal asterisks.

  • strikethrough: (boolean) [default false] Enable support for strikethrough syntax. ~~strikethrough~~ as <del>strikethrough</del>

  • tables: (boolean) [default false] Enable support for tables syntax. Example:

    | h1    |    h2   |      h3 |
    | 100   | [a][1]  | ![b][2] |
    | *foo* | **bar** | ~~baz~~ |

    See the wiki for more info

  • tablesHeaderId: (boolean) [default false] If enabled adds an id property to table headers tags.

  • ghCodeBlocks: (boolean) [default true] Enable support for GFM code block style.

  • tasklists: (boolean) [default false] Enable support for GFM tasklists. Example:

     - [x] This task is done
     - [ ] This is still pending
  • smoothLivePreview: (boolean) [default false] Prevents weird effects in live previews due to incomplete input

  • smartIndentationFix: (boolean) [default false] Tries to smartly fix indentation problems related to es6 template strings in the midst of indented code.

  • disableForced4SpacesIndentedSublists: (boolean) [default false] Disables the requirement of indenting sublists by 4 spaces for them to be nested, effectively reverting to the old behavior where 2 or 3 spaces were enough. (since v1.5.0)

  • simpleLineBreaks: (boolean) [default false] Parses line breaks as <br>, without needing 2 spaces at the end of the line (since v1.5.1)

    a line  
    wrapped in two

    turns into:

    <p>a line<br>
    wrapped in two</p>
  • requireSpaceBeforeHeadingText: (boolean) [default false] Makes adding a space between # and the header text mandatory (since v1.5.3)

  • ghMentions: (boolean) [default false] Enables github @mentions, which link to the username mentioned (since v1.6.0)

  • ghMentionsLink: (string) [default{u}] Changes the link generated by @mentions. Showdown will replace {u} with the username. Only applies if ghMentions option is enabled. Example: @tivie with ghMentionsOption set to //{u}/profile will result in <a href="//">@tivie</a>

  • encodeEmails: (boolean) [default true] Enable e-mail addresses encoding through the use of Character Entities, transforming ASCII e-mail addresses into its equivalent decimal entities. (since v1.6.1)

    NOTE: Prior to version 1.6.1, emails would always be obfuscated through dec and hex encoding.

  • openLinksInNewWindow: (boolean) [default false] Open all links in new windows (by adding the attribute target="_blank" to <a> tags) (since v1.7.0)

  • backslashEscapesHTMLTags: (boolean) [default false] Support for HTML Tag escaping. ex: \<div>foo\</div> (since v1.7.2)

  • emoji: (boolean) [default false] Enable emoji support. Ex: this is a 😄 emoji For more info on available emojis, see (since v.1.8.0)

  • underline: (boolean) [default false] EXPERIMENTAL FEATURE Enable support for underline. Syntax is double or triple underscores ex: __underlined word__. With this option enabled, underscores are no longer parses into <em> and <strong>.

  • completeHTMLDocument: (boolean) [default false] Outputs a complete html document, including <html>, <head> and <body> tags' instead of an HTML fragment. (since v.1.8.5)

  • metadata: (boolean) [default false] Enable support for document metadata (defined at the top of the document between ««« and »»» or between --- and ---). (since v.1.8.5)

    var conv = new showdown.Converter({metadata: true});
    var html = conv.makeHtml(someMd);
    var metadata = conv.getMetadata(); // returns an object with the document metadata
  • splitAdjacentBlockquotes: (boolean) [default false] Split adjacent blockquote blocks.(since v.1.8.6)

NOTE: Please note that until version 1.6.0, all of these options are DISABLED by default in the cli tool.


You can also use flavors or presets to set the correct options automatically, so that showdown behaves like popular markdown flavors.

Currently, the following flavors are available:

  • original - original markdown flavor as in John Gruber's spec
  • vanilla - showdown base flavor (as from v1.3.1)
  • github - GFM (GitHub Flavored Markdown)





CLI Tool

Showdown also comes bundled with a Command Line Interface tool. You can check the CLI wiki page for more info

Integration with AngularJS

ShowdownJS project also provides seamlessly integration with AngularJS via a "plugin". Please visit for more information.

Integration with TypeScript

If you're using TypeScript you maybe want to use the types from DefinitelyTyped

Integration with SystemJS/JSPM

Integration with SystemJS can be obtained via the third party "system-md" plugin.

Integration with VueJS

To use ShowdownJS as a Vue component quickly, you can check vue-showdown.

XSS vulnerability

Showdown doesn't sanitize the input. This is by design since markdown relies on it to allow certain features to be correctly parsed into HTML. This, however, means XSS injection is quite possible.

Please refer to the wiki article Markdown's XSS Vulnerability (and how to mitigate it) for more information.


Showdown allows additional functionality to be loaded via extensions. (you can find a list of known showdown extensions here) You can also find a boilerplate, to create your own extensions in this repository

Client-side Extension Usage

<script src="showdown.js" />
<script src="twitter-extension.js" />

var converter = new showdown.Converter({ extensions: ['twitter'] });

Server-side Extension Usage

var showdown    = require('showdown'),
    myExtension = require('myExtension'),
    converter = new showdown.Converter({ extensions: ['myExtension'] });


A suite of tests is available which require node.js. Once node is installed, run the following command from the project root to install the dependencies:

npm install

Once installed the tests can be run from the project root using:

npm test

New test cases can easily be added. Create a markdown file (ending in .md) which contains the markdown to test. Create a .html file of the exact same name. It will automatically be tested when the tests are executed with mocha.


If you wish to contribute please read the following quick guide.

Want a Feature?

You can request a new feature by submitting an issue. If you would like to implement a new feature feel free to issue a Pull Request.

Pull requests (PRs)

PRs are awesome. However, before you submit your pull request consider the following guidelines:

  • Search GitHub for an open or closed Pull Request that relates to your submission. You don't want to duplicate effort.

  • When issuing PRs that change code, make your changes in a new git branch based on master:

    git checkout -b my-fix-branch master
  • Documentation (i.e: changes can be made directly against master.

  • Run the full test suite before submitting and make sure all tests pass (obviously =P).

  • Try to follow our coding style rules. Breaking them prevents the PR to pass the tests.

  • Refrain from fixing multiple issues in the same pull request. It's preferable to open multiple small PRs instead of one hard to review big one.

  • If the PR introduces a new feature or fixes an issue, please add the appropriate test case.

  • We use commit notes to generate the changelog. It's extremely helpful if your commit messages adhere to the AngularJS Git Commit Guidelines.

  • If we suggest changes then:

    • Make the required updates.
    • Re-run the Angular test suite to ensure tests are still passing.
    • Rebase your branch and force push to your GitHub repository (this will update your Pull Request):
    git rebase master -i
    git push origin my-fix-branch -f
  • After your pull request is merged, you can safely delete your branch.

If you have time to contribute to this project, we feel obliged that you get credit for it. These rules enable us to review your PR faster and will give you appropriate credit in your GitHub profile. We thank you in advance for your contribution!

Joining the team

We're looking for members to help maintaining Showdown. Please see this issue to express interest or comment on this note.


Full credit list at

Showdown is powered by:



评论 (0)

2016/06/10 07:29


showdown.js是一个javascript环境下markdown语法解释工具. ```js new Showdown.converter().makeHtml('#hello markdown!'); ```

2018/12/26 09:36

AGC005_E Sugigma The Showdown

题面翻译 Sigma 和 Sugim在玩一个游戏。 给你两棵树,初始Sigma站在一棵树的编号为x的节点上,Sugim站在另一棵树的编号为y的节点上。Sigma和Sugim轮流行动(第一轮Sigma行动,第二轮Sugim行动),每次行动他们会移动自己所在树的相邻节点上。如果某次行动过后他们站在相同编号的节点上,则游戏结束。Sigma想让游戏尽可能持久,Sugim想让游戏尽快结束。问游戏会在第几轮行动后结束,如果不会结束则输出-1。 思路 如果你知道如何判...

2018/10/30 23:57


概述 juc包中引入了ExecutorService的概念,用来方便我们处理异步任务,不用直接创建Thread对象,并且能管理线程池,不用自己去创建线程,当一个任务执行完之后,这些池里的线程能够复用。JDK里的线程池对象都是实现了ExecutorService接口。 构建 JDK提供了Executors工具类能够让我们方便快捷的创建不同类型不同功能的ExecutorService实例,比如: 关闭 ExecutorService是不会自动关闭的,每当里面的任务被执行完之后,这些线程...

2020/04/02 12:02


一.使用markdown编辑器 1.安装mavon-editor插件 npm install mavon-editor --save 2.在main.js中引入mavon-editor import mavonEditor from 'mavon-editor' import 'mavon-editor/dist/css/index.css' 注:引入index.css是为了解决编辑器的功能显示问题 不引入index.css的异常: 正常引入index.css: 3.在vue中use一下mavon-editor Vue.use(mavonEditor) 4.在html标签中引入mav-editor标签 <mavon-editor v-model=...

2013/01/08 13:14

【CF 应用开发大赛】JSBlog 博客系统

应用名称:JSBlog 博客系统 应用URL地址: 应用说明及使用场景:jsblog 是款开源的 JavaScript 博客程序,不仅可以运行在 GAE、 BAE、OpenShift、CloudFoundry 、Github上,也可以运行在标准 Web容器上。 应用所使用的技术及软件:JavaScript、Markdown、jQuery、Highlight、Backbone、Bootstrap、Mustache、Showdown 等。 创新点(亮点): 该博客使用纯静态页面 使用Markdown格式编写博客 应用...

2019/05/20 13:28


需求:   SW1和SW2分别通过g0/0/13、g0/0/14、g0/0/15接口互联,把这三个接口绑定成一个逻辑接口,SW2为主动端,两台设备之间最大带宽为2G,g0/0/13作为备用链路;   当SW2上的活动接口g0/0/14或者g0/0/15down了,g0/0/13立刻可以成为活动接口,如故障接口恢复,g0/0/13在十秒钟后变为备用状态; 拓扑: 配置:   SW1配置: inter eth-trunk 1 mode lacp-static lacp timeout fast lacp preempt enable ...

2018/10/19 23:04


Markdown是一种可以使用普通文本编辑器编写的标记语言,通过类似HTML的标记语法,它可以使普通文本内容具有一定的格式。Markdown的语法简洁明了、学习容易,而且功能比纯文本更强,因此有很多人用它写博客。 # 一、MarkDown简介及其基本语法 ## 1、MarkDown简介 Markdown 是一种轻量级的「标记语言」,它的优点很多,目前也被越来越多的写作爱好者,撰稿者广泛使用。看到这里请不要被「标记」、「语言」所迷惑,Markdown 的语法...

2020/07/13 12:48


读取不同的格式 平常我们接触的文件格式除了浏览器可以很轻松解决的如图片、音视频等。还有如 word、pdf、excel、markdown、psd、zip 等格式的文件,需要借助库来实现转换才能被浏览器正常的读取及下载.毕竟自己去写这样的解析库还是要考虑 ROI 的嘛! jsPDF 领先的浏览器端解决方案,支持不同类型的PDF文件格式,包括:文本,数字,图形,图片,同时可以自由的编辑PDF中的标题或其它类型元素。...

2018/10/22 10:10


精品源码 Eureka精品源码 Quartz系列全集 xxl-job系列 sharding-jdbc精品源码合集 构建sleuth+zipkin全链路监控系统(完结篇) 前言 前面几篇文章中,我们了解了spring是如何解析@Service,@Reference注解的,今天主要讲的是服务暴露者的一个非常重要的类,ServiceBean , 每个暴露出去的服务都会生成一个ServiceBean. ServiceBean 该类的继承实现关系如下 public class ServiceBean<T> extends ServiceConfig<T> implement...

0 评论
0 收藏