CSV → JSON — spreadsheets to typed API payloads

Choose delimiter and whether row one holds headers; uneven rows pad deterministically with warnings — no silent truncation beyond documented drops.

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CSV → JSON — spreadsheets to API-ready arrays
Covers delimiter guessing UX plus deterministic padding behaviour.

Developer notes

• Parser rejects unclosed quotes loudly. • Extra columns trimmed with warnings — review toast output. • All cell values remain strings — cast numbers/bools in your service.

When teams pick this route

• Glueing CRM CSV dumps into fetch() bodies. • Importing vendor grids before JSON Schema validation.

About these options

CSV exports: choose a delimiter (Auto follows locale — semicolon on /fr), RFC-minimal vs always-quoted fields, line endings, and whether to emit a header row. CSV imports: delimiter + whether row 1 holds column names (Auto delimiter follows locale only for convenience). JSON output (XML, YAML, or CSV sources): indentation (including compact one-line) and optional recursive key sort. JSON → XML: toggle pretty-printing and indent width. YAML output: indent width, readable vs tighter layout, and deterministic string quoting (there is no source YAML file to “preserve”). XML comments are not represented in the intermediate JSON tree.

Worked examples

Header row

Sample input

sku,qty A1,3 B2,1

Sample output

[ { "sku": "A1", "qty": "3" }, { "sku": "B2", "qty": "1" } ]

Semicolon regional file

Sample input

id;city 1;Paris

Sample output

(Toggle delimiter to semicolon or open /fr defaults)

Navigate related converters

Go hierarchical with CSV → YAML, markup via CSV → XML, or revisit JSON → CSV for exports.

CSV → JSON FAQ

Parser guarantees

Why strings only?

CSV carries opaque text — FastMinify avoids guessing numeric types.

Embedded newlines inside quotes?

Supported when wrapped in double quotes per RFC-style parsing.

UTF-8 BOM?

Stripped automatically.

Multiple header rows?

Only row one participates — preprocess upstream.

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CSV to JSON — spreadsheets to API-ready arrays