TSV to CSV converter

TSV to CSV changes tab separators to commas after our table engine has parsed each row, which matters when a quoted TSV field itself contains a tab.

Converted with Table engine · nothing stored
Free: 5 conversions a day · 5 MB each
Higher limits →

From real runs

What you get — and what changes

Element	Result	What happens
Tab delimiters	Changed	Separating tabs were replaced by commas, while the tab inside the quoted note cell remained part of the value.
Header row	Kept	id, name, note, zip, and active remained the output header names in the same order as the TSV source.
Embedded tab text	Kept	The value tab inside was written inside a CSV field without quoting because a literal tab is not a CSV delimiter.
Leading zeros	Changed	The TSV values 001 and 02134 became 1 and 2134 after scalar inference, matching the CSV output we inspected.
Unicode characters	Kept	Zoë was written as UTF-8 text in the CSV output, with no replacement characters in the downloaded file.
Boolean words	Changed	true and false were interpreted as booleans and serialized back as lowercase CSV tokens.

Tab delimiters Changed
Separating tabs were replaced by commas, while the tab inside the quoted note cell remained part of the value.
Header row Kept
id, name, note, zip, and active remained the output header names in the same order as the TSV source.
Embedded tab text Kept
The value tab inside was written inside a CSV field without quoting because a literal tab is not a CSV delimiter.
Leading zeros Changed
The TSV values 001 and 02134 became 1 and 2134 after scalar inference, matching the CSV output we inspected.
Unicode characters Kept
Zoë was written as UTF-8 text in the CSV output, with no replacement characters in the downloaded file.
Boolean words Changed
true and false were interpreted as booleans and serialized back as lowercase CSV tokens.

Sample conversions

Quoted tab inside a field

Input: TSV row: 001\tAda\t"tab\tinside"\t02134\ttrue
Output: CSV output: 1,Ada,tab\tinside,2134,true. The inner tab stayed in the note value, not as a comma.

Unicode name row

Input: TSV row: 002\tZoë\tplain\t94105\tfalse
Output: CSV output: 2,Zoë,plain,94105,false with the accented character intact.

A real TSV → CSV run

We converted our TSV sample (226 B) with Table engine on 2026-09-11. It took 1 ms and produced a 281 B CSV file, 1.2× larger than the input. The engine raised no warnings.

Input · sample.tsv · 226 B

4 data rows × 5 columns; header: company stage arr owner close_date

Rows: 4
Columns: 5
Header: company stage arr owner close_date

Output · sample.csv · 281 B

4 data rows × 5 columns; header: company,stage,arr,owner,close_date

Rows: 4
Columns: 5
Header: company,stage,arr,owner,close_date

First lines of the output

csv

company,stage,arr,owner,close_date
Northwind Traders,Proposal,48000,R. Ayers,2026-10-14T00:00:00.000Z
Contoso Ltd,Negotiation,120000,P. Ng,2026-09-30T00:00:00.000Z
Fabrikam,Qualified,22500,R. Ayers,2026-11-02T00:00:00.000Z
Tailspin Toys,Won,64000,M. Okafor,2026-09-03T00:00:00.000Z

Options and when to change them

delimiter: Use this when the source is a tabular text file with a different separator but a .tsv extension.
header: Disable it for headerless TSV logs so the first record is not consumed as field names.
quote: Set a different quote character only for TSV exports that do not use double quotes around protected fields.
encoding: Choose latin1 for legacy TSV files whose accented names decode incorrectly as UTF-8.
newline: Switch to CRLF when the receiving CSV importer expects Windows line endings.

Do it yourself

Python csv module

bash

python - <<'PY'
import csv
with open("input.tsv", newline="", encoding="utf-8") as src, open("output.csv", "w", newline="", encoding="utf-8") as dst:
    reader = csv.reader(src, delimiter="\t")
    writer = csv.writer(dst)
    writer.writerows(reader)
PY

The standard library keeps every field as text, so compare output if you rely on tabular-ir's typed dates or booleans.

TSV to CSV by API or MCP

The HTTP API and the MCP server run the exact engine this page uses (Table engine); the response carries the same warnings the web converter shows. Check support first with GET /api/v1/pairs?from=tsv&to=csv.

curl

curl -X POST https://filetypeconverters.com/api/v1/convert \
  -H "Authorization: Bearer $FTC_API_KEY" \
  -F "file=@input.tsv" -F "from=tsv" -F "to=csv" \
  -F 'options={"delimiter":","}' \
  --output output.csv

Options this engine accepts for TSV → CSV

Key	Applies to	Type	Default
delimiter	Reading TSV	string	,
header	Reading TSV	boolean	true
quote	Reading TSV	string	"
encoding	Reading TSV	utf-8 · latin1	utf-8
delimiter	Writing CSV	string	,
newline	Writing CSV	·

API reference

When this is the wrong conversion

Do not convert TSV to CSV just to open it in Excel if the source already imports cleanly with tab separators.
If cells may contain unescaped tabs from copy-pasted prose, repair the TSV first or move the data into JSON.

TSV to CSV questions

Can TSV fields contain tabs?

They can when the producer quotes the field, and our TSV sample did that successfully. If the tab is not quoted, every parser will treat it as a separator.

Why was the TSV note not quoted in CSV?

The note contained a tab, not a comma or quote. CSV does not require quotes for tabs, so the writer emitted the field plainly.

Is TSV to CSV available as an on-device web conversion?

Yes. TSV to CSV runs through our table engine and finishes in well under a second for files of a few megabytes.