Convert LaTeX to JSON Online

Paste a LaTeX table below, edit it if you need to, and get JSON back. The conversion runs in your browser, so nothing is uploaded, there is no size limit and there is no signup.

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The output will appear here once there is a table to convert.

What LaTeX is

A LaTeX table is a tabular environment: a column specification, ampersands between cells and double backslashes at the end of each row.

Academic papers, theses and anything typeset with LaTeX or written in Overleaf.

What JSON is

JSON is a text format for nested data: objects with named keys, arrays, strings, numbers, booleans and null. It has no date type and no comments.

Every web API, most configuration files and anything that talks to JavaScript.

What changes when you convert LaTeX to JSON

The tabular body is read, rules are dropped, and escaped characters are unescaped. Text wrapped in textbf or emph is reduced to the text itself.

You choose the shape. An array of objects is the default and the one most code expects. A 2D array is smaller. Column arrays suit charting libraries. A keyed object suits lookups by id.

What carries over from LaTeX to JSON

LaTeX records 2 things about a table that JSON has no way to hold.

JSON wants a type for each column, and LaTeX does not record one, so each column is typed from what its values look like. A column of digits that should stay text - a zip code, a phone number, a leading-zero id - is the usual thing to check afterwards.

JSON has no header row. The column names are repeated as keys on every record instead, which is why the result is bigger on disk than the table it came from.

Anything visual in the LaTeX - weight, alignment, colour, column widths - has no counterpart in JSON and is dropped. The values are what survives.

This is the direction that recovers structure: LaTeX has no table in it to read, only an arrangement that looks like one, so the rows and columns are inferred rather than read.

The identifier 007 comes out of the JSON as 007. Reading it as a number would have made it 7, and an id that changes value is worse than one that stays text.

The role "Analyst, data" survives with its comma, in one cell rather than split across two. That is the first thing to check in any converted table, and the usual place a JSON file goes wrong.

The quotes around Jonah "Jo" Pryce are escaped with a backslash in the JSON.

A worked example

Three rows of staff data, with an identifier that has a leading zero, a value containing a comma, a value containing quotes and one blank cell. Those are the four places formats disagree, so they are the four places to look.

LaTeX in
\begin{tabular}{lllll}
  \toprule
  id & name & role & started & hours \\
  \midrule
  007 & Halima Yusuf & Analyst, data & 2024-03-15 & 38.5 \\
  012 & Jonah "Jo" Pryce & Engineer & 2025-11-02 &  \\
  104 & Wei Chen & Manager & 2023-06-30 & 40 \\
  \bottomrule
\end{tabular}
JSON out
{
  "staff": [
    {
      "id": "007",
      "name": "Halima Yusuf",
      "role": "Analyst, data",
      "started": "2024-03-15",
      "hours": "38.5"
    },
    {
      "id": "012",
      "name": "Jonah \"Jo\" Pryce",
      "role": "Engineer",
      "started": "2025-11-02",
      "hours": ""
    },
    {
      "id": "104",
      "name": "Wei Chen",
      "role": "Manager",
      "started": "2023-06-30",
      "hours": "40"
    }
  ]
}

Questions

How do I convert LaTeX to JSON?

Paste your LaTeX into the box above or drop the file onto it. Check the table in the grid, then copy or download the JSON from the output panel. It takes one step and the data never leaves your browser.

Why does my table not compile?

The usual cause is a missing package. Booktabs rules need \usepackage{booktabs} in the preamble. Switch the rules option off and the output uses plain \hline instead, which needs nothing.

Why did my zip code lose its leading zero?

Type inference turned the text 07030 into the number 7030. Tablizer leaves inference off by default for exactly this reason, and refuses to convert any value starting with a zero followed by a digit even when it is on.

Is there a limit on file size?

No. The work happens on your own machine, so the limit is your machine's memory rather than an upload cap. A file with tens of thousands of rows converts in a second or two.

Is my data uploaded anywhere?

No. The parsing and generating are done by JavaScript running on this page. You can watch the network tab while you convert and see that nothing is sent.

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