@marianmeres/parse-csv

Simple, reliable in-memory CSV parser. Returns a 2D array of strings.

Features

• Handles quoted fields, escaped quotes (""), and newlines within quotes
• Supports both CRLF and LF line endings
• Custom delimiter support (comma, semicolon, tab, pipe, etc.)
• Automatically strips UTF-8 BOM (common in Excel exports)
• Zero dependencies — fully portable to npm/Node.js
• TypeScript, with full type definitions

Note on portability: This parser intentionally does not use Deno's @std/csv. This is a deliberate choice to keep the package fully portable to npm/Node.js without ecosystem-specific dependencies.

In-memory limitation: The parser loads the entire CSV string into memory and processes it at once. It is not designed for streaming or very large datasets. For typical application data (configs, exports, reports) this is perfectly fine. If you need to process huge files (hundreds of MB+), consider a streaming parser instead.

Design philosophy

This parser intentionally does one thing: it turns a CSV string into a string[][]. That's it. There is no header parsing, no column count validation, and no type coercion. Whether row 0 is a header is a semantic decision — it belongs to the consumer, not the parser. The same goes for ragged rows (real-world CSVs are often messy) and value types (numbers, dates, booleans).

That said, mapping headers to record keys is such a common need that the package ships a thin convenience wrapper — parseCsvWithHeader — so you don't have to write it yourself.

Installation

# Deno
deno add jsr:@marianmeres/parse-csv

# npm
npm install @marianmeres/parse-csv

Quick Start

import { parseCsv } from "@marianmeres/parse-csv";

const csv = `name,age,city
Alice,30,Bratislava
Bob,25,"London"`;

const rows = parseCsv(csv);
// [
//   ["name", "age", "city"],
//   ["Alice", "30", "Bratislava"],
//   ["Bob", "25", "London"],
// ]

Header mode

import { parseCsvWithHeader } from "@marianmeres/parse-csv";

const csv = `name,age,city
Alice,30,Bratislava
Bob,25,"London"`;

const records = parseCsvWithHeader(csv);
// [
//   { name: "Alice", age: "30", city: "Bratislava" },
//   { name: "Bob", age: "25", city: "London" },
// ]

Custom delimiter

// European-style semicolon-separated
const rows = parseCsv("name;age;city\nAlice;30;Bratislava", { delimiter: ";" });

// Tab-separated (TSV)
const rows = parseCsv("col1\tcol2\nval1\tval2", { delimiter: "\t" });

API

parseCsv(text, options?)

function parseCsv(text: string, options?: ParseCsvOptions): string[][];

Parameters:

| Name | Type | Description | | ------------------- | -------- | -------------------------------- | | text | string | Raw CSV string to parse | | options.delimiter | string | Field delimiter (default: ",") |

Returns: string[][] — array of rows, each row an array of field strings.

parseCsvWithHeader(text, options?)

function parseCsvWithHeader(text: string, options?: ParseCsvOptions): Record<string, string>[];

Thin wrapper around parseCsv. Treats the first row as column headers and returns an array of objects keyed by those headers. Missing fields in shorter rows default to "".

Parameters: Same as parseCsv.

Returns: Record<string, string>[] — array of records keyed by header names.

License

MIT