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ct-lines

A command-line tool for counting lines of code, comments, tokens and blank lines in files within a directory.

What is ct-lines?

ct-lines (count lines) is a CLI that walks a directory tree and reports per-file and aggregate counts for lines of code, comment lines, blank lines, and tokens. It's useful for understanding the size and composition of a codebase at a glance — without installing heavyweight static analysis tools.

The Problem It Solves

When working across multiple projects or auditing a new codebase, it's useful to quickly answer: how much code is actually here? What percentage is comments? How many tokens would it cost to send this to an LLM?

Most tools that answer these questions are either too complex to install, too slow on large trees, or don't report token counts at all. ct-lines is a small, fast alternative that runs in seconds and outputs clean, readable summaries.

Core Features

Per-file breakdown

ct-lines ./src

File                     Lines   Code  Comments  Blank   Tokens
─────────────────────────────────────────────────────────────────
src/index.ts               142     98        22     22    1,840
src/parser.ts              310    241        40     29    4,102
src/formatter.ts            87     64        10     13      980
─────────────────────────────────────────────────────────────────
Total                      539    403        72     64    6,922

Aggregate stats

After the per-file table, ct-lines prints a summary section:

Summary
  Total files:    3
  Total lines:    539
  Code:           403 (74.8%)
  Comments:        72 (13.4%)
  Blank:           64 (11.9%)
  Tokens:       6,922

Filtering

ct-lines ./src --ext ts,tsx        # only TypeScript files
ct-lines . --exclude node_modules  # skip directories
ct-lines . --min-lines 50          # only files with 50+ lines

Token counting

Token counts use a GPT-compatible tokenizer approximation, making ct-lines useful for estimating LLM context costs before sending a codebase to an API.

Installation

npm install -g ct-lines

Requirements: Node.js ≥ 18.

Tech Stack

  • TypeScript — strict mode, compiled with esbuild
  • fast-glob — efficient directory traversal
  • meow — CLI argument parsing
  • cli-table3 — formatted terminal table output

Use Cases

  • Auditing a new codebase before a refactor
  • Estimating LLM API token costs for context windows
  • Tracking code growth across a project over time
  • Generating quick reports for technical documentation