chart-term 📊

High-fidelity inline terminal charts, sparklines, line plots, and bar graphs with Unicode Braille (2x4 subpixels), box-drawing axes, and 24-bit Truecolor gradients across macOS, Linux, and Windows.

Designed both as an interactive CLI tool (chart-term / chartx) and an embeddable library for monitoring scripts, DevOps pipelines, metrics loggers, and CLI dashboards.

✨ Features

• 📈 High-Resolution 2D Line Plots: 2x4 subpixel precision per character cell using Unicode Braille (⠡⠤⠒⠊) with auto-scaled axes, Y-axis metric units (K, M), and box-drawing frames (│, ─, └).
• ⚡ Inline Sparklines: Compact 8-level vertical blocks ( ▂▃▄▅▆▇█) for inline log streams and status lines.
• 📊 Horizontal Bar Charts: ANSI truecolor bars with sub-character fractional blocks (▏▎▍▌▋▊▉█), percentage indicators, and sorting.
• 📉 Histograms: Automatic statistical frequency distribution bucketing.
• ⏱️ Gauge & Progress Bars: Compact progress bars for CLI tools and batch operations.
• 🌈 Truecolor Gradients: Smooth color interpolation (cyan, green, yellow, magenta, rainbow, or custom hex #rrggbb).
• 🚰 Pipe-Friendly CLI: Ingest raw numbers, CSV, TSV, JSON arrays, and NDJSON streams directly from stdin.
• 📦 Zero Native Dependencies: 100% pure TypeScript/JavaScript.

🚀 Installation

Global CLI Tool

npm install -g chart-term
# or run directly with npx
npx chart-term 10 25 18 42 30 55
# or using short alias
npx chartx 10 25 18 42 30 55

In Your Project (Library)

npm install chart-term

🛠️ CLI Usage & Examples

1. 2D Line Chart from Numbers or Stdin

chartx 12 18 25 42 38 55 68 74 62 85 99 --title "Traffic Spike" --color rainbow

2. Piped CSV / TSV Metrics

cat metrics.csv | chartx --type bar --color gradient --sort desc --percent

3. Inline Sparklines

echo "1 5 2 8 3 7 4 9 6" | chartx --type sparkline --color gradient

4. JSON / API Streams

curl -s https://api.sampleapis.com/bitcoin/historical | jq '.[].price' | chartx --height 10 --color cyan

5. Histogram Frequency Distribution

seq 1 100 | awk '{print rand()*100}' | chartx --type hist --bins 6 --color magenta

📖 Programmatic Library API (TypeScript & JavaScript)

import { lineChart, sparkline, barChart, histogram, progressBar } from "chart-term";

// 1. High-Density Braille Line Plot
console.log(
  lineChart([10, 25, 18, 42, 30, 65, 80], {
    title: "Server CPU Load",
    width: 50,
    height: 10,
    color: "gradient",
    xlabel: "Time (minutes)",
  })
);

// 2. Inline Sparkline
console.log(
  sparkline([5, 12, 8, 19, 24, 32, 18, 40], {
    title: "Request Latency:",
    color: "cyan",
    showMinMax: true,
  })
);

// 3. Bar Chart
console.log(
  barChart(
    {
      "US-East": 4500,
      "EU-Central": 3200,
      "AP-South": 1800,
    },
    {
      sort: "desc",
      showPercent: true,
      color: "rainbow",
    }
  )
);

// 4. Progress / Metric Bar
console.log(progressBar(85, 100, { label: "Disk Usage:", color: "green" }));

⚙️ Options Reference

| Option | Type | Default | Description | | :--- | :--- | :--- | :--- | | type | "line" \| "sparkline" \| "bar" \| "hbar" \| "hist" \| "progress" | "auto" | Chart format | | color | string \| [string, string] | "cyan" | Preset (rainbow, gradient, cyan, etc.) or Hex | | width | number | 60 (line) / 40 (bar) | Chart width in characters | | height | number | 10 | Line chart height in lines | | title | string | undefined | Header title | | xlabel | string | undefined | X-axis footer label | | ylabel | string | undefined | Y-axis header label | | min / max | number | auto | Scaling bounds | | sort | "asc" \| "desc" \| "none" | "none" | Bar chart sorting | | bins | number | 8 | Histogram bucket count |

🧪 Development & Testing

git clone https://github.com/authoritydmc/chart-term.git
cd chart-term
npm install
npm test
npm run build

🚀 Automated Release & Versioning

1-Click from GitHub Actions

Go to Actions -> Automated Version & Release -> Select patch, minor, or major -> Click Run workflow.

From Terminal

npm run release:patch
npm run release:minor
npm run release:major

📄 License

MIT © 2026 authoritydmc