JSON to TypeScript

How the types are inferred

Each object gets its own interface, named after the key that holds it. Arrays of objects are merged into one interface: a key missing from some items becomes optional (?), and values of different types become a union.

Limits of a sample

The types describe the sample you paste, not every payload the API can return: a field that is always null in the sample is typed null. Review the result before committing it.

Is my data safe?

Yes. Everything runs in your browser — nothing you paste is sent to a server, so payloads with customer data or credentials stay on your machine. Large inputs of several megabytes are processed once you stop typing, without freezing the page.

More data tools

• JSON Formatter — Validate and pretty-print JSON, right in your browser.
• JSON Validator — Check whether JSON is valid and see the exact line and column of the error.
• JSON Diff — Compare two JSON documents by structure and list every added, removed or changed value.
• JSON to CSV Converter — Turn a JSON array into a CSV file, with nested keys flattened into columns.
• CSV to JSON Converter — Turn a CSV file with a header row into a JSON array, with numbers and booleans typed.
• JSON to YAML Converter — Convert JSON into clean, indented YAML for configs and manifests.
• YAML to JSON Converter — Convert YAML to JSON, with anchors, aliases and multi-document files resolved.
• XML to JSON Converter — Convert an XML document into JSON, attributes and repeated elements included.
• JSON to XML Converter — Convert JSON into a well-formed, indented XML document.
• XML Formatter — Pretty-print or minify XML and catch malformed tags, right in your browser.
• SQL Formatter — Format SQL queries with consistent indentation and upper-case keywords, per dialect.