JSON Schema generator
Turn a sample of JSON into a JSON Schema. Paste an object, an array or newline-delimited records and it infers the types, properties and array shapes, merges the fields seen across objects into a required list, and recognises common string formats — email, URL, UUID, date and date-time — across Draft 2020-12, 2019-09 or Draft-07.
Related tools
All JSON, XML & formats tools →JSON Schema generator works straight from this page — free, instant, nothing to install. You will find it under JSON, XML & formats, with CSV to JSON converter and JSON comment remover for the neighbouring cases.
How to use it
- Open the tool — no signup or install needed.
- Enter your input or adjust the available options.
- Get your result instantly, then copy or download it.
Frequently asked questions
What is JSON Schema generator?
Turn a sample of JSON into a JSON Schema. Paste an object, an array or newline-delimited records and it infers the types, properties and array shapes, merges the fields seen across objects into a required list, and recognises common string formats — email, URL, UUID, date and date-time — across Draft 2020-12, 2019-09 or Draft-07.
What does a concrete case look like?
{"id": 1, "name": "Ada"} → {"type":"object","properties":{"id":{"type":"integer"},"name":{"type":"string"}}} — the tool shows every step in between, not just the final figure.
When would I actually use this?
Making a machine-generated blob readable, finding the character where a parse fails, and shrinking a file before it ships.
What is the most common mistake?
Assuming valid means correct. A document can parse cleanly and still have the wrong shape for whatever will read it — validation checks the syntax, not the schema.
How is JSON Schema generator different from CSV to JSON converter?
They sit next to each other but answer different questions: CSV to JSON converter is the one to open when you need it to parse CSV text (with header row) into a JSON array of objects, handling quoted fields. Drop a file in rather than pasting it — it is read in your browser and never uploaded. Pick whichever matches what you're starting from — both are free.
Is there a tool for the next step?
JSON comment remover is the closest one after this: Strip // and /* */ comments from JSONC to make it valid JSON. Drop a file in rather than pasting it — it is read in your browser and never uploaded.
What else is worth having open alongside it?
JSON flattener and JSON formatter — they come up in the same task often enough to be worth a second tab.
Where do the figures come from?
Parsing and serialisation follow each format's specification. Key order and whitespace are not semantically meaningful in JSON or YAML, so a reformatted document is equivalent even when the bytes differ.