Overview
Introduction
A long unbroken string, whether it's an encoded blob or a run-on sentence, is often easier to read or process once it's chunked into regular rows.
Manually counting characters or words to insert breaks at consistent intervals across a long string is slow and easy to miscount.
What Is Line Break Adder?
A line break inserter that splits text into chunks of a fixed size, either N characters or N words, and joins the chunks with newlines.
It runs entirely client-side as part of this site's String Tools collection, so nothing you paste is ever uploaded to a server.
How Line Break Adder Works
In character mode, the tool slices the input into substrings of the chosen length; in word mode, it splits the input on whitespace into words and groups them into chunks of the chosen count, joining each chunk's words with a space.
The transformation happens synchronously in JavaScript the moment you type, with no network round trip involved.
When To Use Line Break Adder
Use it to chunk a long encoded string into fixed-width rows, break a run-on sentence into readable segments, or prepare data for a system that expects a maximum line length.
It's a fast way to get the answer without opening a code editor, a REPL, or writing a one-off script just to check.
Often used alongside Line Break Remover, Line Break Replacer and Word Wrapper.
Features
Advantages
- Supports both character-based and word-based chunking from one tool.
- Predictable, uniform chunk sizes.
- Word mode collapses runs of whitespace while tokenizing, so irregular spacing in the source does not produce unevenly sized chunks.
Limitations
- Character mode can break in the middle of a word, which isn't suitable for prose meant to stay readable.
- Word mode normalizes the gap between words to a single space, so any original alignment or indentation is lost in the process.
Examples
Best Practices & Notes
Best Practices
- Use word mode for prose so words are never split mid-character, and character mode only for fixed-width data formats.
- Use character mode for encoded data such as base64, where the content has no word boundaries worth respecting.
- Pick a width that matches the destination, such as 72 or 80 columns for plain-text email or code comments.
Developer Notes
Character mode uses `input.slice(i, i + count)` in a loop stepping by `count`; word mode first tokenizes with `input.split(/\s+/).filter(Boolean)` and then chunks the resulting array with `words.slice(i, i + count)`, so the two modes share the same chunking loop shape but operate on different units.
Line Break Adder Use Cases
- Chunking a long Base64 or hex string into fixed-width rows
- Breaking a run-on sentence into shorter readable segments
- Preparing text for a system with a maximum line length constraint
Common Mistakes
- Using character mode on prose, which can cut a word in half at an arbitrary point.
- Applying character mode to text containing emoji or other astral characters, where slicing counts UTF-16 units and can cut a character in half.
Tips
- Set count to 76 in character mode to reproduce the classic MIME line-length convention for encoded data.
- Word mode never leaves a partial word, so the final line is usually shorter than the rest rather than landing exactly on the count.