Best Free CSV to JSON Converter
Turn CSV rows into a clean JSON array of objects — free, paste or upload, nothing stored.
100% free
No signup
No watermark
Files processed in memory, never stored
✨
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How it works
- Provide CSV. Paste your CSV text or upload a .csv file.
- Set options. Say whether the first row is a header and choose the delimiter (comma, tab, …).
- Get JSON. Copy the formatted JSON array, or download it as a .json file.
About this tool
CSV to JSON turns tabular CSV data into a JSON array you can use in code or an API. Paste the CSV or upload a .csv file, tell it whether the first row is a header, and pick the delimiter if it isn't a comma. With a header row, each line becomes a JSON object keyed by the column names; without one, each line becomes an array. The output is pretty-printed and ready to copy or download. It parses everything in the request and stores nothing.
What people use it for
- Feed spreadsheet data into an API or app
- Convert an exported CSV into JSON for code
- Turn a contact or product list into structured JSON
- Prototype with real data without writing a parser
Developer API
Automate this tool from your own code. Send a POST request to the endpoint below and get the same result the web tool produces. It is rate-limited per IP and needs no signup — API keys for higher limits are coming.
POST
https://best.free/api/tools/csv-to-json/
| Parameter | Example | Required | Notes |
|---|---|---|---|
text |
name,age\nAda,36 |
Yes | CSV text (or upload a file on the web form). |
delimiter |
, |
No | Field delimiter (use "tab" for TSV). |
header |
True |
No | First row is a header. |
curl -X POST https://best.free/api/tools/csv-to-json/ \
-H 'Content-Type: application/json' \
-d '{"text": "name,age\\nAda,36", "delimiter": ",", "header": true}'import requests
r = requests.post(
"https://best.free/api/tools/csv-to-json/",
json={"text": "name,age\nAda,36", "delimiter": ",", "header": True},
)
print(r.json())const r = await fetch("https://best.free/api/tools/csv-to-json/", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({ text: "name,age\nAda,36", delimiter: ",", header: true }),
});
const data = await r.json();
console.log(data);Response: JSON with the converted array in "json".
{"ok": true, "json": "[\n {\"name\": \"Ada\", \"age\": \"36\"}\n]"}Frequently asked questions
With a header row, each data line becomes a JSON object whose keys are the column names. Without one, each line becomes a plain array of values. You choose which on the form.
Yes. Set the delimiter to a tab for TSV files, or to a semicolon or other character, so European-style and tab-separated exports convert correctly.
Yes. Upload a .csv file up to 100 MB, or paste the text directly — either works, and the output is the same.
Values are kept as strings exactly as they appear in the CSV, which avoids surprises like a leading-zero code being turned into a number. You can cast types in your own code if needed.
Yes. As well as showing the formatted JSON to copy, the tool can return it as a downloadable .json file.
No. The CSV is parsed in the request with the standard library and discarded immediately — nothing is stored, logged or forwarded.
Yes. POST a JSON body to /api/tools/csv-to-json/ and you get a JSON response back — the same engine the web tool uses, so results are identical. It is rate-limited per IP like the web version and needs no signup; API keys for higher limits are coming. See the API section above for ready-to-run curl, Python and JavaScript examples.
Yes — CSV to JSON is completely free, with no watermark on the output and no credit card required.
Yes. It runs in your browser, so CSV to JSON works on phones and tablets as well as desktop — there is no app to install.
No. CSV to JSON works with no signup at all; an optional free account only exists to unlock higher usage limits.