JSON to PDF

Paste your JSON on the left, or choose Open JSON to open a file. The PDF appears on the right as you type, with your data in tables. Choose the page size, orientation and margins above the editor, then choose Download PDF.

No. The converter runs in your browser: it lays out your JSON, and ironpress, compiled to WebAssembly, turns it into a PDF there. The only downloads are the converter itself, fonts for Chinese, Japanese, Korean and emoji when your data needs them, and images at https addresses in your template, which your browser fetches from their own servers.

An object's simple values (text, numbers, true, false and null) go in a table of names and values. A nested object gets a heading of its own, and a list of objects becomes a table with a column for each name, in the order they first appear. A value nested inside a list's table is shown as JSON.

Choose Your template under Layout. Write HTML and CSS on the Template tab, with Liquid tags that print your JSON's values: {{ order_number }} or {{ customer.name }}, and {% for item in items %} to repeat a row for each item. If your JSON is a list rather than an object, the template reads it as data.

Liquid's standard filters, such as date, upcase and times, and the filters DocSpring adds to HTML templates: currency, delimited and pluralize. What a tag prints is escaped, so text in your data can't add HTML; end a tag with | raw to print HTML. Dates print in UTC.

The converter says which line and column it is on, like a missing comma or a comma after the last item, and keeps showing the last PDF until you fix it.

ironpress, an open source HTML to PDF engine written in Rust, which also renders PDFs from our Page Designer, and LiquidJS for templates. Mozilla's PDF.js draws the preview. Their licenses are on our open source licenses page.