Multiline Text to Single Line Converter

Paste your multiline text or upload a TXT or CSV file and instantly join all lines into one single line. Choose a separator such as a space, comma, or semicolon between the original lines, trim leading and trailing whitespace, and download the result as TXT or CSV. Perfect for compressing text from emails, code, or documents into a compact single-line format. All processing runs locally in your browser — nothing is sent to a server.

About the Multiline to Single Line Converter

The Multiline Text to Single Line Converter joins multiple lines of text into one compact single line using the separator of your choice. It is ideal for compressing text from emails, code snippets, documents, or data files into a format that is easy to paste into a query, script, spreadsheet cell, or API call.

⭐ What it does

When you paste or upload text that spans several lines, this tool merges all those lines into a single line. You decide what character or string appears between the joined lines — a space, comma, semicolon, pipe, tab, nothing at all, or any custom string you define.

⚙️ How to use

  1. Paste your multiline text into the Input text field, or click Upload file to load a .txt or .csv file.
  2. Choose a Separator from the dropdown. Select Custom... to type your own separator string.
  3. Enable Trim whitespace per line to remove leading and trailing spaces from each line before joining (recommended).
  4. Enable Skip empty lines to ignore blank lines in the input.
  5. Click Convert to generate the output.
  6. Click Copy to copy the result, or use Download as to save it as a TXT or CSV file.

🔎 Example

Input (3 lines):

apple
banana
cherry

With Comma separator, output becomes:

apple, banana, cherry

With Pipe separator:

apple|banana|cherry

With None separator:

applebananacherry

⭐ Available separators

  • Space — joins lines with a single space (default)
  • Comma (, ) — joins with a comma and space; useful for CSV-style lists
  • Semicolon (; ) — joins with a semicolon and space
  • Pipe (|) — joins with a pipe character; common in database and CLI output
  • Tab — joins with a tab character; useful for TSV-style output
  • None — concatenates lines directly without any character between them
  • Custom — type any string as separator, for example - , ::, or →

⚙️ Options

  • Trim whitespace per line — removes spaces and tabs at the start and end of each line before joining. Enabled by default.
  • Skip empty lines — blank lines in the input are ignored and not included in the output. Enabled by default.

⚠️ Notes

  • All processing happens entirely in your browser — your data is never sent to a server.
  • Both Unix (LF) and Windows (CRLF) line endings are handled correctly.
  • The output is a single line. For very large inputs the result may be a very long string.
  • Uploading a .csv file treats each row as one line and joins them with the chosen separator.

Frequently Asked Questions

It joins multiple lines of text into one single line, using a separator you choose. You can use a space, comma, semicolon, pipe, tab, no separator at all, or define a custom separator string.

Paste your multiline text into the input field or upload a TXT or CSV file. Choose a separator, set your options, and click Convert. The result appears in the output field and can be copied or downloaded.

Yes. Click the Upload file button and select a .txt or .csv file from your computer. The file contents will be loaded into the input field automatically.

You can choose from space, comma, semicolon, pipe, tab, or no separator at all. You can also select Custom to enter any separator string you like.

Yes. Choose "Custom..." from the separator dropdown and type any string you want to appear between the joined lines, such as " - ", "::", or "→".

When enabled, any leading or trailing spaces and tabs are removed from each line before the lines are joined. This prevents unwanted extra whitespace in the output.

When enabled, blank lines in the input are excluded from the output. This is helpful when your text contains empty rows between items.

No. All processing is done entirely in your browser using JavaScript. Your text and uploaded files never leave your device.

Yes. Use the Download as button to save the output as a TXT or CSV file.

If you have a list with one item per line, the comma separator converts it into a comma-separated string you can paste directly into a spreadsheet formula, SQL IN clause, or configuration value.

Yes. Both Unix (LF) and Windows (CRLF) line endings are handled correctly and normalized before joining.

There is no artificial limit. The tool runs entirely in your browser, so performance depends on your device, but it handles large amounts of text without issues.