JSON to CSV
Convert JSON object arrays to CSV without rounding numeric tokens. Combine columns, download locally and import IDs into spreadsheets as text.
Developer toolsJSON formatter
Format, validate and minify JSON without rounding large numbers. Explore a read-only tree, find text and download locally.
Ready when you are.
◎ No uploads. Your input stays here.↗ Free to use. No account needed.⌘ / Ctrl + Enter to run
A worked example
Choose Try an example to run these safe test values with the default settings. Compare the complete result with the expected output below.
Input / settings
{"id":9007199254740993,"amount":1.2300,"name":"Åsa"}Expected result
{
"id": 9007199254740993,
"amount": 1.2300,
"name": "Åsa"
}A LITTLE GUIDANCE
How to use JSON formatter
Paste JSON or open a local JSON file, choose 2 spaces, 4 spaces or Minify, then select Format JSON. Sort object keys if needed. Expand the read-only structure or search the numbered preview; use Copy or Download for the complete result.
Good to know
Numeric precision and notation are preserved; this is not a byte-for-byte copy or a full tree editor. Duplicate keys, comments and trailing commas are rejected. Pasted input is limited to 2 million characters; local files to 2 MB. The tree is bounded and only shown for results up to 100,000 characters; search covers the numbered preview, not the entire large document.
A few quick answers.
Will formatting change large IDs or precise decimals?
Numeric tokens are preserved without converting them to JavaScript floating-point numbers. Duplicate keys are rejected rather than silently overwritten. Formatting changes whitespace; sorting object keys is optional.
Is my input sent to a server?
No. This tool processes your input in your browser. We don't store your text, files or results. Standard website access logs are separate; read our privacy notes.
Can I use it for free?
Yes. No account, subscription or usage credits are required.
How do I keep my result?
Use Copy or Download after running the tool. Inputs are not saved automatically and disappear when you leave or refresh the page.
Data preservation guide
Keep large IDs and precise decimal tokens
JavaScript numbers cannot represent every integer above 9007199254740991. This formatter parses numeric tokens without first converting them to floating-point numbers. Try the example: 9007199254740993 stays exact and 1.2300 retains its trailing zeros. Minify removes formatting whitespace; it does not round these tokens.
Fix ambiguous JSON before formatting
A repeated key such as {"id":1,"id":2} is rejected instead of silently choosing one value. Use double quotes around keys and strings, remove trailing commas and comments, and check the reported error location. Validation checks JSON syntax, not your application schema.
Read-only preview versus full output
The tree helps inspect objects and arrays, but cannot edit them. Find in result highlights matches in the preview (up to 1,000 lines / 200,000 characters). Copy, download and the complete plain-text result use the full output. Sorting changes object-key order, not array order.
Continue the workflow: CSV to JSON → inspect and format JSON → export CSV. Each step runs locally; review your options before converting.
Something not right? Report a problem with this tool. Include the steps, but never passwords or private input.