loctok (npm)

Count LOC (lines of code) and LLM tokens — fast. This npm package is a thin wrapper around the Rust CLI that downloads a prebuilt binary and exposes the loctok command on your system.

Quick Start

npx loctok            # run without installing
# or
npm i -g loctok       # install globally

• Requires Node.js >= 14.
• On install, a small script downloads the correct prebuilt binary for your OS/CPU.

If you prefer to build from source (Rust required):

cargo install loctok

What It Does

loctok scans a directory, respecting .gitignore, and reports:

• lines of code per language (non-empty lines)
• token counts using tiktoken encodings (default: o200k_base)
• output as a summary table, a file tree view, or JSON

It only reads UTF‑8 text files and skips non‑UTF‑8 files silently.

Usage

# Count tokens in the current directory
loctok

# Count tokens in a specific path
loctok path/to/dir

# Choose output format: table (default), tree, json
loctok --format tree
loctok --format json > counts.json

# Choose encoding
loctok --encoding cl100k_base

# Filter by file extensions (comma-separated, no dots)
loctok --ext rs,ts,md

# Include hidden files (dotfiles)
loctok --hidden

# Silence progress output in scripts
loctok --format json 2>/dev/null

# See all options
loctok --help

# Concatenate filtered files and copy to clipboard
loctok copy                  # from current directory
loctok copy path/to/dir      # from a given path

# Copy with filters and also print the content
loctok --ext rs,md --hidden copy --show

Supported encodings: o200k_base (default), cl100k_base, p50k_base, p50k_edit, r50k_base.

Output Examples

Table (default):

> loctok

595.17ms (655.27 files/s)
╭────────────┬───────────────┬─────────────╮
│ Language   │ lines of code │ token count │
├────────────┼───────────────┼─────────────┤
│ Rust       │       109,910 │     894,106 │
│ Other      │        13,705 │     174,612 │
│ ...        │            ...│         ... │
│ SUM:       │       138,280 │   1,262,285 │
╰────────────┴───────────────┴─────────────╯

Tree view:

> loctok --format tree

379.96ms (21.05 files/s)

Name                           LOC       TOK
--------------------------------------------
    ┌── lib.rs                 332     3,213
    ├── main.rs                573     4,707
┌── src/                       905     7,920
...
./                           1,989    20,289

JSON:

{
  "path": ".",
  "encoding": "o200k_base",
  "token_number": 200000,
  "models": ["GPT-4o", "GPT-4.1", "o1", "o3", "o4"],
  "total": 20431,
  "files": [
    { "path": "./Cargo.toml", "lines": 26, "tokens": 201 },
    { "path": "./src/main.rs", "lines": 573, "tokens": 4707 }
  ],
  "by_language": [
    { "language": "Rust", "lines": 974, "tokens": 8710 },
    { "language": "Markdown", "lines": 120, "tokens": 1316 }
  ]
}

Notes:

• Progress updates print to stderr; they are in-place on TTYs and line-based otherwise.
• Token counts use the chosen encoding; token_number and models are informative mapping hints.
• Copy mode requires a platform clipboard tool:
  • macOS: pbcopy
  • Windows: clip
  • Linux: xclip or xsel

Copy Mode

Use copy to bundle filtered files into a single, structured payload that is copied to your clipboard. Optionally print it with --show.

loctok copy [PATH] [--show] [--ext rs,md] [--hidden]

Format snippet:

├── src
│   ├── lib.rs
│   └── main.rs
└── README.md

/src/lib.rs:
--------------------------------------------------------------------------------
1 | use anyhow::{Context, Result};
2 | // ...

Supported Platforms

Prebuilt binaries are provided for:

• macOS: x64, arm64
• Linux (gnu): x64, arm64
• Windows (MSVC): x64

If your platform isn’t covered, build from source with cargo install loctok.

Install Details & Troubleshooting

• This package downloads a prebuilt binary during npm install into an internal vendor/ folder and exposes a small JS shim at bin/loctok.js.
• To use a custom mirror, set LOCTOK_DOWNLOAD_BASE to a base URL that mirrors the GitHub Releases layout.
• If the download fails (e.g., no network), try again or install from source: cargo install loctok.

License

MIT or Apache-2.0