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CSV to JSON converter

Paste CSV data with headers and instantly get a clean JSON array of objects. Runs entirely in your browser — nothing is sent to a server.

Output

What is CSV to JSON conversion?

CSV to JSON conversion transforms flat, tabular data into structured objects that web applications, APIs, and modern data tools consume natively. Each row becomes a JSON object, and each column header becomes a key.

This is a common step when migrating data from spreadsheets or legacy systems into applications that expect JSON, or when preparing configuration and seed data for web projects.

When to convert CSV to JSON

  • Preparing data for consumption by REST or GraphQL APIs
  • Building configuration files or seed data for web applications
  • Transforming spreadsheet exports for use in JavaScript or Python
  • Converting flat data into nested structures for data pipelines

How type detection works

CSV is inherently untyped — every value is a string. When type detection is enabled, this tool inspects each value and converts it to the most appropriate JSON type: numeric strings become numbers, true and false become booleans, and empty strings become null. This saves a manual post-processing step and produces cleaner JSON that's ready to use directly.

From JSON data to instant dashboards

If you're converting CSV to JSON as part of a data pipeline or analytics workflow, Basedash can skip the transformation entirely. Connect your data source and describe the chart or metric you want in plain English — Basedash writes the query, runs it, and renders the visualization in seconds.

FAQ

What CSV formats are supported?

This tool supports RFC 4180 standard CSV including quoted fields, escaped quotes, and multiline values within quotes.

Is my data stored or sent to a server?

No. All conversion happens entirely in your browser using JavaScript. Your data is never transmitted, logged, or stored anywhere.

How does type detection work?

When enabled, numeric strings are converted to numbers, "true" and "false" become booleans, and empty strings become null. You can toggle this off to keep all values as strings.

Does it detect the delimiter automatically?

Yes. Auto-detect mode tries comma, tab, semicolon, and pipe and picks the best match. You can also set the delimiter manually.

Does the first row need to be headers?

Yes. The first row is used as object keys in the JSON output. Each subsequent row becomes an object in the array.

Is there a size limit?

No hard limit. The converter handles files up to several MB comfortably. Very large files may be slow depending on your browser.

Related tools

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