CSV to YAML Converter
Free online CSV to YAML converter. Paste spreadsheet data or drop a CSV file and get clean, valid YAML instantly — with type inference, dot-notation nesting, custom delimiters, and live preview. No signup, no server: 100% client-side.
CSV input
YAML output
How to convert CSV to YAML
Paste or upload CSV
Drop a .csv file, paste spreadsheet data, or load a sample. The delimiter is detected automatically.
Adjust options
Toggle the header row, type inference, and dot-notation nesting; pick block or flow YAML style and indent size.
Copy or download
The YAML updates live. Copy it to your clipboard or download it as a .yaml or .yml file.
Built for real YAML, not just text
Correct quoting, always
Values YAML would misread — yes, 007, 12:30 — are quoted automatically, and multiline cells become proper block scalars.
Smart type inference
Numbers, booleans, and nulls are detected per cell while original text is preserved, so precision is never lost.
Dot-notation nesting
Headers like server.host fold into nested mappings — flat spreadsheets become hierarchical configs in one step.
Flexible roots & styles
Emit a sequence of maps, a mapping keyed by the first column, block style, or compact flow style.
Delimiter auto-detect
Comma, semicolon, tab, and pipe are detected from your data; a custom delimiter option covers the rest.
Private by design
Parsing and generation run entirely in your browser. Nothing is uploaded — safe for sensitive data.
Example: CSV becomes YAML
# CSV input id,user.name,user.address.city,active,notes 1,Alice,Paris,true,"Line one Line two" 2,Bob,Berlin,false,On-call # YAML output (headers with dots nest automatically) - id: 1 user: name: Alice address: city: Paris active: true notes: |- Line one Line two - id: 2 user: name: Bob address: city: Berlin active: false notes: On-call
CSV to YAML converter FAQ
What is a CSV to YAML converter?
A CSV to YAML converter is an online tool that turns comma-separated spreadsheet data into YAML, the human-readable format used for configuration files and data exchange. Each CSV row becomes a YAML mapping keyed by the header row, so tabular data converts into structured YAML you can paste straight into configs, CI pipelines, or API payloads.
How do I convert CSV to YAML online?
Paste your CSV into the input box or drop a .csv file onto it, and the YAML output updates live as you type. Tune the options if needed — delimiter, header row, nesting, output style — then copy the result or download it as a .yaml or .yml file. No signup and no waiting.
How are CSV headers turned into YAML keys?
By default the first CSV row becomes the YAML keys for every record. Headers with dots create nested mappings automatically, so user.address.city becomes a nested user > address > city structure. Turn nesting off if you want literal dotted keys, or disable the header row to get generic col1, col2 keys instead.
Does the converter detect numbers and booleans automatically?
Yes. Type inference is on by default: 30 becomes the number 30, true becomes a boolean, and empty cells become null. Numbers keep their original text so precision is never lost. Strings that YAML would misread — like yes, 007, or 12:30 — are always quoted to protect their meaning. You can switch inference off to keep every cell a string.
How are multiline CSV cells converted to YAML?
Cells containing line breaks become YAML literal block scalars (the | style), which is the correct way to represent multiline strings in YAML. The converter picks the right chomping indicator (|-, |, or |+) so the value round-trips exactly, including trailing newlines.
Which CSV delimiters are supported?
The delimiter is auto-detected from comma, semicolon, tab, and pipe, which covers CSV, TSV, and European-style semicolon files. You can also force a specific delimiter or type a custom one. Comment lines starting with # are skipped, and there is an option to ignore empty lines.
Can I download the YAML as a .yaml or .yml file?
Yes. Use the download button and pick the .yaml or .yml extension — the file is generated locally in your browser, so even large conversions download instantly with no server round-trip.
Is this CSV to YAML converter free?
Yes. This is a free CSV to YAML converter with no signup, no usage limits, and no watermarks. Everything runs locally in your browser, so there is no server queue and no waiting time.
Does my CSV data leave my browser?
No. The CSV parser and YAML generator are 100% client-side JavaScript with zero external requests. Your data is never uploaded, stored, or sent anywhere, which makes this tool safe for sensitive spreadsheets and internal datasets.
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