Commas inside values now need quoting
A field like "Kyiv, Ukraine" needed no special treatment in a TSV. In CSV it must be quoted, which the converter does automatically — but it is why the file is not just a search and replace.
Convert TSV to CSV
Tab-separated files come out of databases, bioinformatics tools and older exports. Converting to CSV is mostly about quoting: values that were safe between tabs may contain commas, and those now need escaping properly.
- Runs in your browser
- No signup
- No upload
- Free
TSVCSV
Runs on your deviceCSV
Options
Reading TSV
Auto-detect reads the first rows and picks the separator that splits them consistently.
Turn off when the file starts straight into data. Columns are then named column_1, column_2, and so on.
Turns "42" into a number and "true" into a boolean. Values with leading zeros stay text so IDs and zip codes survive.
Which worksheet to convert. Filled in once the workbook is read.
Dotted path to the array of records, such as data.items. Leave empty to use the whole document.
Turns {"user":{"id":7}} into a user.id column. Arrays are kept as JSON text.
Pick the encoding the file was written in. Wrong encoding shows up as garbled accents.
Comma-separated words that should become null instead of text.
Writing CSV
Snappy is the default across Spark, DuckDB and pandas. Gzip is smaller but slower to read.
Turns a user.id column back into {"user":{"id":7}}.
Excel needs a byte order mark to open UTF-8 files with accents correctly.
Rows per row group. Larger groups compress better; smaller groups let readers skip more.
Converting…
Ad slot ·
conversion-preroll
This short ad is what keeps the converter free.
Work with Parquet as well?See ParquetReader with ParquetReader — opens Parquet files directly.What happens
How this converter handles TSV to CSV
- Splits on tabs, honouring quoted fields.
- Re-escapes every value for CSV, quoting anything containing a comma, a quote or a newline.
- Keeps the header row and the column order unchanged.
- Optionally adds a BOM so Excel reads UTF-8 correctly.
Format differences
TSV vs CSV
Like CSV, but tab-delimited, so commas inside values stay harmless. Plain text rows that open anywhere, with no types and no schema.
| TSV | CSV | |
|---|---|---|
| Type information | None — every value is text | None — every value is text |
| Structure | Flat rows and columns | Flat rows and columns |
| Compression | None | None |
| Typical file size | Same as CSV | Baseline (100%) |
| Schema | Header row at best | Header row at best |
| Human-readable | Yes, in any text editor | Yes, in any text editor |
| Tool support | Universal | Universal |
Worth knowing
What to watch out for
TSV was arguably the safer format
Tabs almost never appear inside data values, while commas appear constantly. If the destination accepts TSV, keeping it avoids a whole class of quoting bugs.
Some TSV dialects do not quote at all
Strict TSV forbids tabs and newlines in values instead of quoting them. If your file uses backslash escapes rather than quotes, check a few rows of the output.
When you need this
Common reasons to convert TSV to CSV
Feeding a tool that only accepts CSV
Plenty of importers list CSV and nothing else.
Normalising a mixed set of exports
One delimiter across a folder of files makes downstream scripts simpler.
Sharing with people who will open it in Excel
Excel handles .csv without an import dialog; .tsv often triggers one.
FAQ
TSV to CSV questions
Is my file uploaded?
No. The conversion runs in your browser using WebAssembly and JavaScript. The file is read from your disk into a Web Worker, converted in memory, and handed back as a download. It is never sent to a server, so there is nothing for us to store, log or leak.
What is the actual difference between TSV and CSV?
Only the delimiter — a tab instead of a comma. The practical difference is that tabs rarely occur inside real values, so TSV files need far less quoting.
Will values containing commas break?
No. Any value containing a comma, a quote or a newline is quoted to RFC 4180, and embedded quotes are doubled.
Can I output a different delimiter, like a pipe?
Yes — pick it in the output options. Pipe and semicolon are both available.
Will it open in Excel?
Yes. Enable the BOM option if the data contains non-ASCII characters.
Keep going