An AsciiMath parser and MathML/LaTeX generator written in pure Ruby.


Build Status Gem Version


Add this line to your application’s Gemfile:

gem 'asciimath'

And then execute:

$ bundle

Or install it yourself as:

$ gem install asciimath



First require the library.

require 'asciimath'

Then parse an AsciiMath string.

parsed_expression = AsciiMath.parse(asciimath)

The parsed expression is a set of nested Array and Hash objects.

This expression can then be converted to MathML, HTML (experimental) or LaTeX.

math_ml = parsed_expression.to_mathml
html = parsed_expression.to_html
latex = parsed_expression.to_latex

The MathML, HTML or LaTeX code is returned as a String.

Command line

The AsciiMath parser and converters can be invoked via the command line as follows:

MathML Generation
asciimath "an asciimath string"


asciimath mathml "an asciimath string"
HTML Generation
asciimath html "an asciimath string"
LaTeX Generation
asciimath latex "an asciimath string"

This command will print out the generated code on stdout.

Extentions and Customization

The parser can be extended by passing a custum tokenization table:

my_tokens_table =
my_tokens_table.add('mysymbol', :mysymbol, :symbol)

AsciiMath::parse("a + mysymbol + b",

Furthermore, the behaviour of the tokenizer be customized by altering the value associated with a token in AsciiMath::Tokenizer::DEFAULT_PARSE_SYMBOL_TABLE:

my_tokens_table =
my_tokens_table.add('alpha', :beta, :symbol)

# Now "alpha + beta" is equivalent to "beta + beta"
AsciiMath::parse("alpha + beta",

The same behaviour applies to each individual render (MathMLBuilder, HTMLBuilder and LatexBuilder). By adding entries to a rendere’s rendering table (or modifying exisisting entries), users can customize it’s output:

my_rendering_table =
my_rendering_table.add('alpha', '\u03b2', :identifier)

# Now "alpha + beta" is equivalent to "beta + beta"
AsciiMath::parse("alpha + beta").to_mathml(

Notes on the HTML Output

The HTML output is still regarded somewhat experimental - for basic usage it is fine, but it is not yet complete. Known issues are as follows:

  • sqrt function does not generate sane output

  • Use of font commands (e.g. bb) will result in broken output.

  • Accents do not extend to match what they cover.

  • Rendering of "integrals" uses a generic path that does not look amazing.

  • The size of braces does not account for complex content - so a matrix will render with the right sized braces if all of its elements are single-height text, but braces around e.g. fractions will render at the incorrect height.

Rendering the HTML output correctly requires the inclusion of style/math.css in the html document. There is currently no specific required font for this output, it simply selects a serif font family - change the @font-family attribute in the .math-inline class to select something specific.

Notes on the LaTeX Output

All LaTeX commands and environments used in the output are coverved by amsmath and amssymb, with a few exceptions:

  • \color

  • \cancel

  • \mathscr

  • \twoheadrightarrowtail

The \color command is supported by the xcolor package, which is included in most LaTeX distributions. The \cancel command is supported by the cancel package, also included in most LaTeX distributions. The other commands are supported by the stix package.


  1. Fork it (

  2. Create your feature branch (git checkout -b my-new-feature)

  3. Commit your changes (git commit -am 'Add some feature')

  4. Push to the branch (git push origin my-new-feature)

  5. Create a new Pull Request