How to Convert CSV to TSV (Tab-Separated Values)

What CSV to TSV Conversion Means

Converting CSV to TSV replaces the field separator (usually a comma) with a tab character. Rows still exist per line. Headers still work the same way.

The point of TSV is not to be exotic. It is to remove the constant quoting pressure that comma-heavy fields create.

name,city,notes
"Nguyen, Minh",Toronto,"VIP, renew soon"

name	city	notes
Nguyen, Minh	Toronto	VIP, renew soon

When to Prefer TSV Over CSV

TSV shines whenever tabs are rare in your data but commas are common.

• Address lists and product titles.
• Notes fields, descriptions, and free text.
• Exports for bioinformatics and analytics tools that prefer TSV.
• Anything that reduces awkward quoting downstream.

What Stays the Same After Conversion

TSV inherits the CSV idea of one record per line and an optional header row.

Step-by-Step: Convert CSV to TSV

Handle quoting correctly—do not simply search-and-replace commas with tabs.

• Preview the CSV in the Online CSV Editor.
• Confirm delimiter and encoding first.
• Use the CSV to Delimited Converter and pick tab as the output separator.
• Preview the TSV output.
• Verify that fields containing commas are now correctly separated by tabs.
• Download the TSV file with a .tsv or .txt extension.

import csv

with open("input.csv", newline="", encoding="utf-8") as inp, \
     open("output.tsv", "w", newline="", encoding="utf-8") as out:
    reader = csv.reader(inp)
    writer = csv.writer(out, delimiter="\t")
    for row in reader:
        writer.writerow(row)

import fs from "node:fs";
import { parse } from "csv-parse/sync";
import { stringify } from "csv-stringify/sync";

const csv = fs.readFileSync("input.csv", "utf8");
const records = parse(csv, { columns: false, skip_empty_lines: true });
const tsv = stringify(records, { delimiter: "\t" });
fs.writeFileSync("output.tsv", tsv);

Real-World Examples

TSV solves specific problems—use it deliberately.

Common Mistakes

TSV bugs usually come from naive replacements.

• Search-and-replace commas with tabs, breaking quoted fields.
• Renaming .csv to .tsv without changing separators.
• Losing quoting on rare fields that still contain tabs.
• Mixing tab and space separators after manual edits.

Best Practices

Do TSV once and document it.

• Use quote-aware conversion tools or CSV libraries.
• Name files honestly (.tsv).
• Keep UTF-8 encoding.
• Verify the first and last rows after conversion.
• State the delimiter in a README when files travel between teams.

Why Use Convert CSV Online?

Delimiter conversion needs a fast, previewable workflow. Convert CSV Online is free, browser-based, and requires no account for everyday conversions. Use the CSV to Delimited Converter to pick tab (or any other separator), and use the Online CSV Editor to verify the result. Client-side processing works across Windows, macOS, and Linux browsers.

Conclusion

CSV to TSV is a deliberate choice for comma-heavy text data. Use quote-aware tools, verify the output, and document the separator downstream.