Is my CSV data uploaded to a server?

No. The conversion runs entirely in your browser with JavaScript. Nothing is sent over the network, which makes the tool safe for sensitive data.

How are numbers and booleans typed?

Typing is conservative: clear numbers and booleans are converted, but values with leading zeros (like ZIP codes) stay strings.

Does it work with files exported from Excel?

Yes. The Excel byte order mark (BOM) at the start of the file is detected and handled automatically.

100% local — your data never leaves your browser

CSV to YAML Converter — Free Online Tool

Convert CSV with headers to a YAML sequence instantly in your browser. Free, private and offline-friendly: your data never leaves your device.

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Indentation

Delimiter

Swap: YAML → CSV

CSV input

YAML output

Why convert CSV to YAML?

Spreadsheets export CSV, but configuration files and fixtures are often YAML. Paste your CSV with a header row above and get a YAML sequence of mappings in milliseconds, one mapping per row.

How it works

The converter parses your CSV locally, using the header row as keys, and emits a YAML sequence of mappings. Numbers and booleans are typed conservatively — values with leading zeros remain strings — and the Excel BOM is handled automatically.

Frequently asked questions

Is my CSV data uploaded to a server?: No. The conversion runs entirely in your browser with JavaScript. Nothing is sent over the network, which makes the tool safe for sensitive data.
How are numbers and booleans typed?: Typing is conservative: clear numbers and booleans are converted, but values with leading zeros (like ZIP codes) stay strings.
Does it work with files exported from Excel?: Yes. The Excel byte order mark (BOM) at the start of the file is detected and handled automatically.