Line counts are a rough but useful measure of a codebase: they help estimate review effort, track growth over time, and compare the size of modules. A plain line count, however, treats blank lines and comments as if they were code, which inflates the figure and hides the real amount of logic. This counter separates pasted source into total lines, code lines, comment lines and blank lines, using comment syntax for common languages, including line comments and block comments. The result is a fairer picture of how much code is actually there, and it is useful for reports, estimates and code review planning without needing to install any tooling.
Quick Answer: Paste source code and click Count Lines to see totals for code, comment and blank lines separately.
Free Online Tool
Code Line Counter
Code, comment and blank lines, counted separately.
How to Use the Code Line Counter
- Paste your source code into the input box, in any common language.
- Click Count Lines to analyse every line as code, comment or blank.
- Read the four totals and the code share, which shows what fraction of the file is real logic.
- Compare totals across files to spot unusually comment heavy or unusually dense modules.
- Copy the summary into a report or estimate where a plain line count would be misleading.
Key Features
- Four way breakdown: total, code, comment and blank lines reported separately.
- Line comment support for double slash and hash style comments used by many languages.
- Block comment support, tracking comments that span multiple lines until their closing marker.
- Code share percentage, showing the proportion of the file that is executable logic.
- Local processing, so proprietary source code pasted here never leaves your browser.
Best Practices and Tips
- Use the code line count, not the total, when estimating review time, since comments and blanks need far less scrutiny.
- A very high comment share is not a flaw by itself, but it is worth checking whether the comments explain why rather than restating what.
- Compare code counts before and after a refactor to confirm the change genuinely simplified the module.
- Strip generated files from your totals, since machine generated code can dwarf hand written code in a misleading way.
Common Mistakes to Avoid
- Quoting a total line count as a productivity measure, which rewards verbose code and penalises concise solutions.
- Counting minified or generated files alongside source files, which distorts every comparison.
- Forgetting that a line can contain both code and a trailing comment; this tool counts such lines as code, which is the standard convention.
Frequently Asked Questions
How are lines classified?
Blank lines contain only whitespace. Comment lines contain only a comment, either a line comment or text inside a block comment. Lines with code, including code followed by a trailing comment, count as code lines. The four categories always add up to the total line count.
Which comment styles are supported?
Line comments starting with double slash or a hash, and block comments delimited by slash star and star slash, covering the conventions of JavaScript, Python, C style languages and many others. Language specific documentation comments that use those same markers are counted as comments, which is the intended behaviour.
Why not just use a word counter?
A word counter counts words in prose, not structure in code. It cannot distinguish a comment from a statement, and it treats a long line of code the same as a long sentence. A code aware counter understands the syntax markers that separate logic from annotation.
Is a higher line count better?
No. Line counts measure size, not quality. Concise, well tested code is usually better than verbose code that does the same job, and the value of this tool is in honest measurement for planning, not in ranking developers by output.