CSV looks simple until a value contains a comma, a quote, or a line break. This tool applies the RFC 4180 rules to escape a single field so it round-trips correctly, and unescapes a quoted field back to its raw value.
How it works
A field is quoted only when it must be, and embedded quotes are doubled:
needs quoting if field contains: delimiter, double quote, or newline
escape: wrap in " ... " and replace every " with ""
"plain" -> plain (no special chars, left bare)
a,b -> "a,b" (comma forces quoting)
6" pipe -> "6"" pipe" (quote doubled)
line1\nline2 -> "line1\nline2" (newline forces quoting)Unescaping detects a field wrapped in double quotes, strips the outer pair, and
collapses every "" back to a single ".
When do you need to escape a CSV field?
Most of the time you don’t — if a field contains only letters, numbers, and punctuation other than the delimiter, no quoting is required. You need to escape when the value includes:
- The delimiter character — a comma (or semicolon, or tab) inside the value would split the row at the wrong place.
- A double quote — the parser uses
"to start and end quoted fields, so a literal"inside must be doubled to"". - A line break — a bare
\nor\r\nwould end the CSV record mid-field; quoting the field keeps the line break as part of the value (useful for multi-line addresses or notes).
Practical examples
| Raw value | Escaped (comma delimiter) | Why |
|---|---|---|
plain text | plain text | No special characters, no quoting needed |
London, UK | "London, UK" | Comma forces quoting |
6" pipe | "6"" pipe" | Quote is doubled inside quoted field |
Line 1\nLine 2 | "Line 1\nLine 2" | Newline forces quoting |
{a: 1} | {a: 1} | Curly braces are not special in CSV |
Delimiter choice and regional conventions
The tool supports comma, semicolon, and tab delimiters:
- Comma — the default in most English-language tools.
- Semicolon — standard in many European countries where the comma is the decimal separator (Germany, France, the Netherlands). Excel on a German system exports with semicolons by default.
- Tab — produces TSV; tabs in values are very rare in practice, making quoting unnecessary in most files.
The formula injection caveat
RFC 4180 escaping makes a field parse correctly as a data value. It does not prevent formula injection in spreadsheet tools. A value beginning with =, +, -, or @ is treated as a formula by Excel and Google Sheets when the file is opened, regardless of quoting. For CSV destined for spreadsheets, prefix such values with a single quote or a space, or configure the spreadsheet to import the column as text.
Quote only when necessary — over-quoting every field is legal but bloats the file and hurts readability. All processing runs in your browser; nothing is uploaded.