What separators can I use?

Common choices include a comma followed by a space, a pipe with surrounding spaces, a semicolon plus space, plain space, tab, no separator (direct concatenation), or any custom string. The tool typically lets you specify any string as the separator.

Will it preserve formatting?

By default the tool joins lines as-is and preserves whitespace within each line, unless you turn on trimming. Some implementations offer options to trim each line before joining, skip empty lines, or normalize whitespace.

How does it differ from a CSV converter?

Joining is simple line concatenation. CSV is a structured format with headers, rows, and escaping rules. Joining is more general and works for any single-line conversion, while CSV is a specific format with its own conventions.

Can I handle quotes within lines?

The tool usually passes content through unchanged. For proper CSV-quoted output that handles commas inside cells, use a CSV-specific tool — the join tool stays simpler and does not auto-quote.

Empty lines: include or skip?

This is typically configurable. The default usually includes empty lines to preserve the original structure. Skipping them produces cleaner output but loses any intentional separation, so choose based on your use case.

What's the reverse operation?

Splitting lines, which converts a single line back into multiple lines, is the paired functionality. Some tools bundle both directions; others keep them separate. The reverse is useful for expanding CSV cells back into a list or breaking apart comma-separated input.

Is the data sent to a server?

No. Line joining is pure JavaScript text manipulation that runs entirely in your browser. Your text never leaves your device.

Join Lines

Join multiple lines into one string online with custom delimiters. Free line joiner for merging text lines with commas or spaces.

Text Tools

Instant results

Separator

Trim linesRemove empty

Input (one item per line)

Joined Output

About Join Lines

Join multiple lines into a single line with a separator. Great for creating comma-separated lists, SQL IN clauses, or any list format.

How to Use Join Lines

Paste multi-line text

Drop in the text with multiple lines — a list, a data export, or anything you copied that needs to become a single line.

Choose separator

Pick comma plus space, pipe, semicolon, space, a custom string, or no separator at all. Match the output to the target format, whether that is CSV, prose, or code.

Configure options

Optionally trim whitespace from each line and skip empty lines. The defaults work for most cases.

Copy result

The tool joins everything into a single line. Copy it to the clipboard and paste into a CSV cell, your code, or any single-line input field.

When to Use Join Lines

Data formatting and CSV preparation

Converting multi-line data into a single line covers a lot of ground — CSV cells with multi-value content, single-field form inputs, log analysis where each entry needs to be one line, and configuration values that have to be inline. The tool joins with a custom separator while preserving the underlying content, which is exactly what data preparation pipelines, format conversions between systems, ETL workflows, and normalization tasks need.

Code and text manipulation

Sometimes you need verbose multi-line code collapsed into a single line — SQL queries that span multiple lines, regex patterns broken across lines, JSON arrays expressed as comma-separated values, or compact code for embedded contexts. This shows up in code golf, single-line code generation, command-line argument preparation, and pasting code into chat tools that handle single-line input better than multi-line.

Email signatures and contact formatting

Address blocks and signatures often need to flip between comma-separated single line and multi-line block formats. The tool joins with whichever separator you choose, which makes it handy for contact list imports that require single-line addresses, vCard generation, email signature formatting, business card text preparation, mailing label generation, and CRM data entry.

Data cleanup and normalization

Lists copied from various sources tend to have inconsistent line formatting, and the tool normalizes them down to a single line for further processing. This is the typical pre-analysis cleanup, and it also fits content copy-pasted out of PDFs and Word docs, formatted text with extraneous line breaks, single-line input for downstream tools, and scraped data heading into a database.

Join Lines Examples

With comma separator

Input

Apple\nBanana\nCherry

Output

Apple, Banana, Cherry

Standard list joining with a comma-and-space separator. This is the right choice for prose lists, CSV cells, and contact data.

With pipe separator

Input

Item 1\nItem 2\nItem 3

Output

Item 1 | Item 2 | Item 3

A pipe separator is common for alternative formats, breadcrumb-style lists, and data display where commas would be ambiguous.

No separator

Input

Multi-line\ntext

Output

Multi-linetext (joined directly) OR Multi-line text (with space).

The separator is configurable. None means direct concatenation; a single space gives word-like joining. The tool typically lets you choose between the two.

Tips & Best Practices for Join Lines

1.Choose your separator based on the destination. CSV wants a comma; prose lists want comma plus space; code depends on the language; custom can be any string you like.
2.Watch trailing and leading whitespace. The tool can trim before joining or preserve it, so configure that based on what you need.
3.If a CSV cell ends up containing commas, quote the result. 'A, B, C' as a single cell becomes '"A, B, C"', and the tool may handle this automatically.
4.Decide whether empty lines should be skipped or included. The tool usually offers an option, and empty lines sometimes carry intentional separation that skipping would lose.
5.For HTML output, using <br> as the separator preserves line breaks visually while still being technically a single line.
6.The reverse operation, splitting lines, is the paired tool. Some implementations bundle both directions; others keep them separate.

Frequently Asked Questions

It joins multi-line text into a single line using whichever separator you choose. It is the inverse of splitting lines, and the typical use cases are data formatting, converting lists into prose, preparing CSV cells, and compacting code.

Join Lines

About Join Lines

How to Use Join Lines

Paste multi-line text

Choose separator

Configure options

Copy result

When to Use Join Lines

Data formatting and CSV preparation

Code and text manipulation

Email signatures and contact formatting

Data cleanup and normalization

Join Lines Examples

With comma separator

With pipe separator

No separator

Tips & Best Practices for Join Lines

Frequently Asked Questions

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