CSV to JSON
Convert comma-, semicolon- or tab-separated data to JSON. Keep leading zeros and text values, inspect the result and download locally.
Developer toolsJSON to CSV
Convert JSON object arrays to CSV without rounding numeric tokens. Combine columns, download locally and import IDs into spreadsheets as text.
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,"code":"001","name":"Åsa"},{"id":9007199254740995,"note":"new column"}]Expected result
id,code,name,note 9007199254740993,001,Åsa, 9007199254740995,,,new column
A LITTLE GUIDANCE
How to use JSON to CSV
Paste a non-empty JSON array of objects or open a local JSON file. Choose comma, semicolon or tab, decide whether to include column names, and keep formula protection enabled for untrusted data. Convert, then download the CSV. Import identifier columns as text in your spreadsheet.
Good to know
Nested objects and arrays become JSON text in cells, not separate columns. Missing keys, null and empty strings all export as empty cells, so a round trip cannot restore those distinctions. Numeric tokens are not rounded, but spreadsheet apps can reinterpret them. Files are limited to 2 MB and pasted input to 2 million characters.
A few quick answers.
Why does a spreadsheet formula get a leading apostrophe?
Formula protection prevents spreadsheet apps from executing cells beginning with formula characters. Disable it only for trusted data. Large numeric tokens are preserved in the CSV, but a spreadsheet may still round them when opening the file; import identifiers as text.
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
Columns are the union of object keys
A key appearing only in a later object still becomes a column. The example produces id, code, name and note columns; absent keys become empty cells. Arrays and objects nested inside a row are quoted JSON text. This is not a flattening or schema-inference tool.
Preserve identifiers when opening the file
The exported CSV contains the full 9007199254740993 token and the string 001. Double-clicking a CSV in a spreadsheet can round a long ID or drop leading zeros. Use the spreadsheet import flow, choose the delimiter and set identifier columns to Text before loading. Quoting alone does not force spreadsheet text types.
Formula protection and round-trip limits
Protection prefixes cells beginning with formula-triggering characters such as =, +, - or @ with an apostrophe. This changes the exported value deliberately, including negative numeric text, and reduces formula execution risk; it is not a guarantee for every spreadsheet. Disable it only for trusted data. Converting back to JSON produces strings and cannot recover null, missing keys or original types.
Continue the workflow: CSV to JSON → inspect and format JSON → export CSV. Each step runs locally; review your options before converting.
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