Remove empty lines

Remove empty lines and lines made only of spaces and tabs, without changing the other lines. It is handy after copying from a PDF, a spreadsheet or an email that left stray blank lines behind.

The tool goes through the text line by line and removes the lines that contain no meaningful character. The lines it keeps retain their content and order, including spaces at their start or end. Note that blank lines used to separate paragraphs disappear too. The tool removes neither duplicates nor spaces inside lines. A line can look empty yet contain invisible spaces or tabs. The tool removes those lines just like completely empty ones. Do not confuse this operation with a full text clean-up, though: spaces on non-empty lines stay in place and duplicates are not removed. In a list of identifiers, removing empty lines makes counting and importing easier. In an article or a message, the same operation can erase the gaps between paragraphs and make the text harder to read. So decide whether the blank lines are mere copy-and-paste artefacts or a deliberate part of the layout. For code, Markdown or files where empty lines have a function, work on a copy and check the structure afterwards. Windows line endings are converted to plain line feeds, which can alter a file meant for a tool that is sensitive to its exact format. If you would rather reduce repeated spaces inside sentences, use a text cleaner with suitable options. To check the result, count the content lines before and after. The number of non-empty lines should stay the same, even though the text gets shorter. Also look at a few places where two paragraphs used to be separated by a blank line.