JSON formatter
Format, validate and minify JSON without rounding large numbers. Explore a read-only tree, find text and download locally.
Developer toolsCSV to JSON
Convert comma-, semicolon- or tab-separated data to JSON. Keep leading zeros and text values, inspect the result 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,name,note 001,Åsa,"first line second line"
Expected result
[
{
"id": "001",
"name": "Åsa",
"note": "first line\nsecond line"
}
]A LITTLE GUIDANCE
How to use CSV to JSON
Paste CSV or open a local CSV/TSV file. Select the matching delimiter or Detect automatically. Keep First row contains column names enabled for a header row, then choose Convert to JSON. Review the result and download or hand it to the JSON formatter.
Good to know
All field values remain strings, including numbers, booleans and empty cells. Headers must be non-empty and unique; each data row must have the same field count. Rows whose fields are all empty or whitespace are skipped. Local files are read as UTF-8 and limited to 2 MB; pasted input to 2 million characters.
A few quick answers.
Why is a CSV row rejected?
Each row must have the same number of fields as the header. Quote fields containing commas or line breaks. Headers must be non-empty and unique; values remain strings to preserve leading zeroes.
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
Leading zeros are data, not formatting
The example becomes an object with id "001", not the number 1. A CSV field containing true or 42 also stays a string. An empty field becomes ""; the word null stays "null". CSV has no native JSON types, so this converter does not guess them.
Choose the dialect and quote special characters
Use Semicolon for id;name or Tab for a TSV export. Explicit selection is safer than detection for short or single-column files. Enclose a field containing a delimiter or line break in double quotes; represent a quote inside that field as two quotes. UTF-8 accented letters and a leading UTF-8 byte-order mark are supported.
Resolve headers and uneven rows
With headers enabled, id,id is rejected because an object cannot safely represent two values under the same key. With headers disabled, columns become column1, column2 and so on. Add an explicit empty field for a missing cell; a short row is rejected rather than silently shifted. Formatting the resulting JSON does not change its string values.
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.