PDF Command-Line Cheatsheet

A quick reminder of handy PDF tools on Linux (Xubuntu / Ubuntu).

---

## 📘 Combine PDFs

### **Using `pdfunite`**

```bash
pdfunite file1.pdf file2.pdf file3.pdf output.pdf
```

➡️ Merge multiple PDFs into one.
*(Simple and reliable — part of `poppler-utils`)*

---

## ✂️ Extract or Reorder Pages

### **Using `pdftk`**

```bash
# Extract pages 1–3 and 10–12
pdftk input.pdf cat 1-3 10-12 output subset.pdf
```

### **Using `qpdf`**

```bash
# Extract pages 5–10
qpdf input.pdf --pages . 5-10 -- output.pdf
```

---

## 📄 Split into Single Pages

### **With `pdftk`**

```bash
pdftk input.pdf burst
```

➡️ Creates one file per page: `pg_0001.pdf`, `pg_0002.pdf`, etc.

---

## 🔍 Check PDF Info

### **With `pdfinfo` (from poppler-utils)**

```bash
pdfinfo file.pdf
```

### **With `qpdf`**

```bash
qpdf --show-npages file.pdf
```

➡️ Shows the number of pages.

---

## 🧩 Combine Extracted Pieces

### **Using `qpdf`**

```bash
qpdf part1.pdf part2.pdf --pages . 1-z -- combined.pdf
```

---

## 🧰 Install the Tools

```bash
sudo apt install poppler-utils pdftk qpdf
```

---

### 💡 Tip

If `pdftk` gives Java errors, use:

```bash
sudo snap install pdftk
```

That installs the stable legacy version.