Comma Separator
Convert any list to a comma-separated (CSV) line — or turn CSV back into a clean line-by-line list. Choose delimiter, quotes, prefixes/suffixes, text case, and cleanup options like remove duplicates or whitespace. Fast, accurate, and free with higher daily limits.
Comma Separator
The Comma Separator converts a line-by-line list into a single delimited string, or converts a delimited string back into a clean vertical list. Paste your items, configure the delimiter, quoting, prefix, suffix, text case, and cleanup options, then click Generate List. The output is formatted and ready to paste directly into Excel, Google Sheets, a SQL query, a programming array, a CRM import, or any other tool that expects separated values.
Most data import processes require values to arrive in a specific format. A spreadsheet import expects comma-separated values in a single row. A SQL WHERE IN() clause expects values in parentheses with quotes. A JavaScript array expects values in square brackets with double quotes. Writing these formats by hand for lists of any length is slow and error-prone. The Comma Separator handles the formatting automatically, whatever the target format requires.
How to use the Comma Separator
- Paste your items into the input box — one item per line. The tool treats each line as a separate value.
- Choose a Delimiter — the character that will separate items in the output. Comma is the default. See the delimiter reference table below for guidance on when to use each option.
- Optionally configure List Prefix and Suffix (characters that wrap the entire output, such as ( and ) for SQL, or [ and ] for arrays) and Item Prefix and Suffix (characters added before and after every individual item).
- Choose a Quotes option — None, Double, or Single — to control whether each value is wrapped in quote marks in the output.
- Select any cleanup options needed — Remove Duplicates, Remove Line Breaks, Remove Double Spaces, Remove All Whitespace, Reverse List, or Text Case conversion. Click Generate List. Copy the result.
Bidirectional conversion: the tool works in both directions. To convert a comma-separated string back into a vertical list (one item per line), paste the CSV string into the input and use the appropriate reverse operation. This is useful when you receive data as a comma-separated string and need to edit individual items, then reconvert to CSV format.
Delimiter options — which to use and when
The delimiter is the character placed between each item in the output. The correct choice depends entirely on the target format — what system or tool will consume the output. The table below covers all delimiter options with guidance on their specific use cases:
| Delimiter | Character | Primary uses | Notes |
| Comma | , | CSV files, spreadsheet imports, SQL IN() clauses, keyword tags | The universal default for data exchange. Accepted by Excel, Google Sheets, most databases, and virtually all import tools. Wrap values in quotes if any item contains a comma. |
| Comma + space | , | Readable lists, copywriting, HTML attributes | Adds a space after each comma. Produces more readable output for human-facing text. Less suitable for machine parsing where trailing spaces can cause errors. |
| Semicolon | ; | European CSV files, some database systems, Outlook email imports | The standard CSV delimiter in European locales where the comma is used as the decimal separator. Required by some email platforms and legacy database export tools. |
| Tab | \t | TSV (Tab-Separated Values) files, Excel paste, log analysis | Tab-separated output pastes directly into spreadsheet columns in Excel and Google Sheets. Standard for TSV files and many analytics and BI tool exports. |
| Pipe | | | Log file parsing, database imports, configuration files | Useful when data contains commas (avoiding the need to quote every value). Common in Unix/Linux log formats and certain CRM and ERP import specifications. |
| Space | Shell commands, configuration values, simple inline lists | Produces space-separated output. Useful for command-line arguments and some configuration file formats where comma is not the expected delimiter. | |
| None (no gap) | Concatenated tokens, domain/username generation, code strings | Joins all items directly with no separator between them. Used with the Word Combiner workflow when creating domain slugs, combined identifiers, or concatenated codes. |
European vs international CSV: in countries where the comma is used as the decimal separator (most of continental Europe), CSV files conventionally use the semicolon as the field delimiter instead of the comma. If you are creating CSV files for European users or importing into systems configured for a European locale, use the semicolon delimiter. If a CSV file opens incorrectly in Excel — all values appearing in a single column rather than separate columns — the delimiter mismatch is almost always the cause.
All configuration options — what each one does
The Comma Separator provides twelve configuration options beyond the delimiter itself. Each option serves a specific purpose. The table below explains every option and identifies the situations where it is most useful:
| Option | What it does | When to use it |
| List Prefix / Suffix | Adds a fixed string at the very beginning and/or very end of the entire output. | Creating array notation: add [ before and ] after the output for JavaScript/Python array syntax. Add ( before and ) after for SQL IN() clauses. Example: ([apple,banana,mango]) |
| Item Prefix / Suffix | Adds a fixed string before and/or after every individual item in the output. | Adding a common path or namespace to every item: prefix 'users/' turns [apple, banana] into [users/apple, users/banana]. Adding currency symbols, units, or ID prefixes to every value. |
| Quotes: None | Items are output without any quote characters around them. | Numeric values, IDs, and any data that does not need quoting. Output: 1,2,3 or apple,banana,mango |
| Quotes: Double | Wraps each item in double quote marks. | Standard CSV format for string values. Required for strings in JSON arrays. Output: "apple","banana","mango" |
| Quotes: Single | Wraps each item in single quote marks. | SQL string values: WHERE name IN ('apple','banana','mango'). Python string lists. Certain config file formats that expect single-quoted values. |
| Text Case: Uppercase | Converts all output items to UPPERCASE. | Country codes, currency codes, product SKUs, database column names, environment variable names, and any standard that requires uppercase identifiers. |
| Text Case: Lowercase | Converts all output items to lowercase. | URL slugs, CSS class names, tag lists, email addresses, and any context where consistent lowercase is required for matching or display. |
| Reverse List | Reverses the order of items (last item becomes first). | Reversing chronological data (newest first), reversing priority order, or when a downstream process expects data in the opposite sequence to the source. |
| Remove Line Breaks | Strips any blank lines from the input before processing. | Cleaning pasted data from spreadsheets or documents that include blank rows between entries. Prevents empty values appearing in the output. |
| Remove Double Spaces | Replaces any occurrence of two or more consecutive spaces with a single space. | Cleaning data copied from PDFs, formatted documents, or text where the formatting introduced extra spaces. |
| Remove All Whitespace | Removes all spaces from within each item. | Processing phone numbers, postal codes, account numbers, or any identifier where spaces must be stripped for matching or import. Use with care — also removes intentional spaces within multi-word items. |
| Remove Duplicates | Removes repeated items, keeping only the first occurrence of each value. | Cleaning keyword lists, email lists, tag lists, or any imported data that may contain duplicate entries. Essential before importing into databases or CRM systems where unique values are required. |
Output examples for common use cases
The table below shows eight of the most common use cases with the specific settings combination required to produce the correct output format. All examples use the same four-item input list: apple, banana, mango, orange.
| Use case | Settings used | Output example |
| SQL WHERE IN() clause | Delimiter: comma | Quotes: Single | List Prefix: ( | List Suffix: ) | ('apple','banana','mango','orange') |
| JavaScript array | Delimiter: comma | Quotes: Double | List Prefix: [ | List Suffix: ] | ["apple","banana","mango","orange"] |
| Python list (strings) | Delimiter: comma+space | Quotes: Single | List Prefix: [ | List Suffix: ] | ['apple', 'banana', 'mango', 'orange'] |
| CSV for spreadsheet import | Delimiter: comma | Quotes: Double | No prefix/suffix | "apple","banana","mango","orange" |
| Tag/keyword list | Delimiter: comma+space | Quotes: None | Text Case: Lowercase | apple, banana, mango, orange |
| TSV for Excel paste | Delimiter: Tab | Quotes: None | No prefix/suffix | apple[TAB]banana[TAB]mango[TAB]orange |
| Clean deduped email list | Delimiter: comma | Remove Duplicates: on | Remove All Whitespace: on | user (at) a.com,user (at) b.com,user (at) c.com |
| URL path segments | Delimiter: / | Quotes: None | Text Case: Lowercase | apple/banana/mango/orange |
Practical use cases
SQL WHERE IN() queries
The SQL IN() operator filters database query results to rows where a column value matches any item in a provided list. The syntax requires values to appear in parentheses, separated by commas, with string values wrapped in single quotes: WHERE name IN ('apple','banana','mango'). When working from a spreadsheet column or a copied list of IDs, names, or codes, converting them manually to this format for even a 20-item list takes several minutes and introduces transcription errors. The Comma Separator produces correctly formatted IN() content in one step: set the delimiter to comma, quotes to Single, List Prefix to ( and List Suffix to ).
Spreadsheet and database imports
Importing data into Excel, Google Sheets, Airtable, or a database typically requires a CSV file or a single row of comma-separated values. Data often arrives in the wrong format — a vertical list copied from a document, a column exported from a tool without commas, or a tab-separated export that needs comma conversion. The Comma Separator converts the list to the required format, with cleanup options to handle the common issues that accompany real-world data: blank lines, double spaces, and duplicate entries that would create problems during import.
Programming arrays and configuration
Developers frequently need to convert plain text lists — from a spreadsheet, a requirements document, or a colleague's email — into correctly formatted array syntax for use in code. A JavaScript string array requires double quotes and square brackets: ["item1","item2"]. A Python list requires single quotes and square brackets: ['item1','item2']. A SQL IN() clause requires single quotes and parentheses. The Comma Separator produces all of these formats by combining the delimiter, quotes, and prefix/suffix options. No manual editing required after generation.
Keyword and tag list formatting
SEO keyword lists, CMS tag fields, YouTube video tags, and social media hashtag sets all require values to be submitted as comma-separated strings. When keyword research produces a vertical list of terms, converting to a clean comma-separated format for pasting into a CMS tag field or an ad platform keyword input takes one step with the Comma Separator. The Remove Duplicates option eliminates any repeated terms from merged keyword lists before conversion. The Text Case option standardizes all terms to lowercase, which is the conventional format for tags and lowercase-sensitive systems.
Email list and data cleaning
Email marketing platforms, CRM systems, and outreach tools often require contact lists to be uploaded as comma-separated values. Lists compiled from multiple sources frequently contain duplicates, inconsistent spacing, and blank entries. The Comma Separator's cleanup options — Remove Duplicates, Remove Line Breaks, Remove Double Spaces, Remove All Whitespace — can clean a raw list before conversion in the same step, producing import-ready output without a separate cleaning stage.
Usage limits
| Guest users | 25 uses per day. No account required. |
| Registered users | 100 uses per day. Free to register — higher limit and usage history included. |
Related tools
- Word Combiner — generate every combination between two word lists, then use the Comma Separator to format the output as a CSV or SQL-ready string.
- Word Counter — count the words and items in your list before or after conversion.
- Case Converter — convert the capitalization of list items before pasting into the Comma Separator, or use the Text Case option within the Comma Separator directly.
- Keyword Research Tool — research keywords and then use the Comma Separator to format the resulting keyword list for import into an ad platform or CMS.
- Related Keywords Finder — generate a list of related terms, then use the Comma Separator to format them as a tag list, array, or SQL IN() clause.
Frequently asked questions
What is a comma separator tool?
A comma separator tool converts a vertical list of items (one item per line) into a single line of delimiter-separated values, or converts a delimited string back into a vertical list. It automates the formatting that would otherwise require manually typing a comma after every item, adding quote marks, and wrapping the output in brackets or parentheses. The ToolsPiNG Comma Separator also includes cleanup options (remove duplicates, remove whitespace, remove blank lines) and formatting options (text case, quotes, custom prefix/suffix) to produce output that is ready for its intended destination without further editing.
What is the difference between CSV and TSV?
CSV (Comma-Separated Values) uses a comma to separate items: apple,banana,mango. TSV (Tab-Separated Values) uses a tab character: apple[TAB]banana[TAB]mango. TSV is particularly useful when values may contain commas — for example, addresses or full names — since the tab character rarely appears within data values. TSV output pastes directly into separate spreadsheet columns in Excel and Google Sheets when you paste as plain text. Select the Tab delimiter in the Comma Separator to produce TSV output.
How do I format a list for a SQL WHERE IN() clause?
Set the delimiter to Comma, Quotes to Single, List Prefix to ( (opening parenthesis), and List Suffix to ) (closing parenthesis). Click Generate List. The output will be in the format ('value1','value2','value3') which can be pasted directly after WHERE column_name IN in any standard SQL query. For numeric values (IDs, integers), set Quotes to None — SQL does not require quotes around numeric values in IN() clauses.
Can I convert a comma-separated list back into a vertical list?
Yes. The tool works in both directions. To convert a comma-separated string back to a line-by-line list, paste the CSV string into the input area. The tool identifies the delimiter and reformats the output as separate lines. This is useful when you receive data as a CSV and need to review, edit, or clean individual items before reconverting.
What does the Remove Duplicates option do?
Remove Duplicates scans the input for repeated lines and keeps only the first occurrence of each value, discarding any subsequent repeats. This is particularly useful when merging lists from multiple sources — for example, combining a keyword list from two different research sessions, or consolidating an email list from several imports — where the same item may appear more than once. Removing duplicates before conversion prevents them from appearing in the output and causing issues during database import or CMS upload.
When should I use single quotes vs double quotes?
Use Double quotes when the output is destined for JSON, CSV (RFC 4180 standard), or JavaScript string arrays. Double quotes are the JSON standard and the most widely accepted string delimiter in CSV files. Use Single quotes when the output is destined for SQL string values — SQL convention uses single quotes for string literals in queries. For numeric data (IDs, integers, prices), use None — neither SQL nor most import formats require quotes around numeric values, and adding them can cause type mismatch errors.
What does the List Prefix/Suffix do, and what does Item Prefix/Suffix do?
List Prefix and Suffix wrap the entire output — they appear once at the very start and very end of the complete converted string. Use these for array notation: [ and ] for JavaScript/Python arrays, ( and ) for SQL IN() clauses. Item Prefix and Suffix appear before and after every individual item in the output. Use these when every item needs a common leading string (a path, a namespace, a currency symbol) or a common trailing string (a unit, an extension, a suffix). For example, setting Item Prefix to /api/v1/ would prepend that path to every item in the list.
Is the Comma Separator free?
Yes. The tool is free within the daily usage limits. Guest users can run 25 conversions per day without creating an account. Registering a free ToolsPiNG account increases the daily limit to 100 uses and gives access to usage history and saved favorites.