CSVFixLab
CSV Guide

CSV delimiters: comma, semicolon, tab, and pipe

A delimiter separates fields. The safe way to change it is to parse the CSV first and serialize the fields again — not replace characters blindly.

Quick answer: A CSV delimiter is the character that separates fields in each record. Comma is the conventional separator, but real exports may use semicolons, tabs, or pipes. If a file imports as one giant column, confirm the delimiter before editing the data.

What is a CSV delimiter?

A delimiter is the separator between fields. The name “comma-separated values” suggests one separator, but real-world exports often use semicolons, tabs, or pipes. Tab-separated files are usually called TSV, yet some systems still save other delimiter styles with a .csv extension.

Comma, — the conventional CSV separator and the format many importers expect.
Semicolon; — common in locales where a comma is used as the decimal separator.
Tab\t — typically called TSV and useful when text values contain many commas.
Pipe| — used by some exports and data pipelines when commas or tabs are inconvenient.

Why semicolon-separated CSV files are common

Some regional settings use a comma as the decimal separator. A semicolon can then be used as the field separator so a value such as 19,95 does not conflict with column boundaries. This is one reason a file that looks fine in a local spreadsheet can import as a single column elsewhere.

sku;title;price
A1;Blue Shirt;19,95
A2;Red Shirt;24,50

What a pipe-delimited file looks like

sku|title|price
A1|Blue Shirt|19.99
A2|Red Shirt|24.50

A pipe-delimited file is structurally similar to CSV, but the separator is |. If the destination expects commas, convert the parsed fields rather than replacing every pipe in the raw text.

Delimiter detection should use consistent structure

A detector can compare candidate characters and ask which one produces a stable number of fields across multiple records. One row is not enough evidence: free-text values, addresses, and descriptions can contain commas or other punctuation that are not separators.

If nearly every row resolves to one field, the parser may be using the wrong delimiter. If only a few rows have the wrong width, the problem is more likely to be a local quote or delimiter error. See the CSV column count mismatch guide.

Quoted delimiters do not split fields

sku,title,description
A1,"Blue, Large","Cotton shirt"

The comma inside "Blue, Large" belongs to the field because the value is quoted. A correct delimiter conversion must parse the CSV first and then serialize it again. Replacing every semicolon or comma in the raw text can corrupt valid field contents.

How to convert a CSV delimiter safely

  1. Detect or confirm the source delimiter. Check several rows, not just the header.
  2. Parse the file using CSV quoting rules. Delimiters inside quoted fields must remain data.
  3. Verify a consistent field count. Stop if records have structural mismatches that need investigation.
  4. Serialize the parsed fields with the destination delimiter. Do not use blind character replacement.
  5. Quote values when needed. If a value contains the destination delimiter, line breaks, or quotes, serialize it correctly.
  6. Re-open or re-parse the output. Confirm that the converted file still represents the same fields.

Signs that the delimiter is wrong

  • The importer shows one giant column instead of many.
  • The header line appears as one field.
  • Every row has the same text width but the parser reports one column.
  • A semicolon file opens correctly in a regional spreadsheet but not in a web importer.
  • The destination expects commas but the raw file consistently uses tabs, pipes, or semicolons.

When the delimiter is not the only problem

If rows resolve to different column counts after the correct delimiter is selected, the file likely has a quoting or structural issue too. Use the Column Count Checker and Broken Quote Checker.

Try it: Detect and normalize a CSV delimiter locally in your browser. For a conservative full-file repair workflow, see Safe CSV Repair.

Frequently asked questions

Is a semicolon-separated file still CSV?

Many applications informally call semicolon-separated exports CSV, even though the literal separator is not a comma. What matters operationally is whether the destination and parser agree on the delimiter and quoting rules.

What is the difference between CSV and pipe-delimited text?

The main difference is the field separator. CSV conventionally uses commas, while a pipe-delimited file uses |. Both still need a consistent way to represent separator characters that appear inside field values.

Can I change semicolons to commas with Find and Replace?

Not safely in general. A semicolon may be part of a field value, and a comma in the destination format may require quoting. Parse the records first, then serialize them with the new delimiter.

Why does my CSV open as one column?

The application may be using a different delimiter than the file. Check the raw text and import settings before editing the data.

Last reviewed: October 7, 2026. This guide focuses on delimiter structure and safe conversion without changing business values.