JSON to HTML Table Converter — Free Online Tool

You can iterate over the array with Object.keys() on the first element to build the header row, then map each object's values into <td> cells. A minimal implementation uses Array.prototype.map() to generate <tr> rows and joins them inside a <table> tag. For production use, always escape cell values to prevent XSS — replace <, >, and & with their HTML entities.

The most common cause is that the input is not a flat JSON array of objects — nested objects or arrays, a top-level object instead of an array, or inconsistent keys across rows all produce unexpected output. Flatten nested structures first and ensure every element in the array shares the same set of keys. Also check that the JSON is valid using a linter before passing it to the converter.

Yes — most converters and custom implementations support injecting class attributes on the <table>, <thead>, <tbody>, <tr>, and <td> elements. Common patterns include adding class="table table-striped" for Bootstrap or class="w-full border-collapse" for Tailwind. If you are writing your own converter, accept a config object that maps element types to class strings.

Nested objects and arrays cannot be natively represented in a flat two-dimensional table. The two standard approaches are: (1) serialize the nested value to a JSON string and display it in the cell, or (2) flatten the structure beforehand using a library like flat (npm) or a recursive function that produces dot-notation keys such as address.city. Choose option 2 if users need to read or sort on nested fields.

An HTML table renders directly in a browser or email client with markup for headers, rows, and optional styling, while CSV is a plain-text format suited for import into spreadsheets like Excel or Google Sheets. HTML tables support inline styling, hyperlinks, and colspan/rowspan; CSV supports none of these. Use HTML tables when the output will be embedded in a webpage or email, and CSV when the data needs further analysis in a spreadsheet tool.