indiPDF Help

Table of Contents



Getting Started with indiPDF

indiPDF is a powerful PDF editor designed specifically for Linux. It provides all the tools you need to view, annotate, edit, and manage PDF documents with a native GTK-styled interface.

Opening a PDF

There are several ways to open a PDF document:

  • File menu: Click File → Open or press Ctrl+O
  • Toolbar: Click the Open button in the header
  • Welcome screen: Click Open PDF on the welcome screen
  • Recent files: Select from File → Open Recent
  • Double-click: Double-click any PDF file in your file manager
  • Drag and drop: Drag a PDF onto the application window

The Interface

The indiPDF interface consists of:

  • Header bar: Contains Open, Save buttons and search functionality
  • Menu bar: Access to all features via File, Edit, View, and Help menus
  • Tab bar: Switch between multiple open documents
  • Toolbar: Quick access to annotation and editing tools
  • Sidebar: Page thumbnails and clipboard history (toggle with F9)
  • Main viewer: Your PDF document

↑ Go to Top



Saving Documents

Save Options

  • Save (Ctrl+S): Saves the document to its current location. If it’s a new document, you’ll be prompted to choose a location.
  • Save As (Ctrl+Shift+S): Save a copy with a new name or location.
  • Save & Flatten: Permanently embeds all annotations into the PDF. Use this when sharing with others who may not have indiPDF.

Understanding Annotations vs. Flattening

When you save normally, annotations remain editable when you reopen the document in indiPDF. When you Save & Flatten, annotations become permanent parts of the PDF and can no longer be edited, but they’ll be visible in any PDF viewer.

↑ Go to Top



Scrolling and Zooming

  • Scroll: Use your mouse wheel or trackpad to scroll through pages
  • Zoom in: Ctrl++ or Ctrl+Mouse wheel up
  • Zoom out: Ctrl+- or Ctrl+Mouse wheel down
  • Fit to width: Ctrl+0
  • Set default zoom: View → Set Current Zoom as Default

Page Navigation

  • Sidebar thumbnails: Click any thumbnail to jump to that page
  • Search results: Click search results to navigate to matches

Searching

  1. Press Ctrl+F or click the search box in the header
  2. Type your search term
  3. Use Ctrl+G to find next or Ctrl+Shift+G to find previous
  4. Click the X to clear the search

↑ Go to Top



Text Markup Tools

Text markup tools let you highlight, underline, or strikethrough text in your PDF.

Using Text Markup

  1. Select the desired tool from the toolbar: Highlight, Underline, or Strikethrough
  2. Click and drag to select text in the document
  3. The markup is applied automatically when you release the mouse

Changing Colors

Before applying markup, you can change the color using the color picker in the toolbar. The default highlight color is yellow, but you can choose any color you prefer.

Removing Markup

  1. Switch to the Select tool
  2. Click on the markup annotation
  3. Press Delete or Backspace

Tip: You can undo markup with Ctrl+Z. Multi-line selections are undone all at once.

↑ Go to Top



Text Annotations

Add text boxes anywhere on your PDF to add notes, fill in information, or make corrections.

Adding Text

  1. Select the Text tool from the toolbar
  2. Click where you want to place the text
  3. Start typing
  4. Click outside the text box when finished

Formatting Text

While editing text, you can:

  • Change the font family using the dropdown
  • Change the font size using the size selector
  • Change the text color using the color picker
  • Select text within the box and apply different formatting to different parts

Moving and Resizing

  • Move: Click and drag the text annotation
  • Resize: Drag the corners or edges of the text box
  • Edit: Double-click to edit the text content

↑ Go to Top



Comments

Comments let you attach notes to specific text selections, similar to commenting in a word processor.

Adding a Comment

  1. Select the Comment tool from the toolbar (or press Ctrl+M)
  2. Select the text you want to comment on
  3. A comment popup will appear
  4. Type your comment and click outside to save

Viewing Comments

Text with comments is highlighted. Click on the highlighted text to view or edit the comment.

↑ Go to Top



Add clickable hyperlinks to your PDF documents.

Creating a Link

  1. Select the Link tool from the toolbar
  2. Select the text you want to make into a link
  3. Enter the URL in the popup dialog
  4. Click OK to create the link

Links appear with a blue underline and are clickable when viewing the PDF.

↑ Go to Top



Drawing Tools

Freehand Drawing

  1. Select the Draw tool
  2. Choose your color from the color picker
  3. Click and drag to draw
  4. Release to finish the stroke

Eraser

Use the Eraser tool to remove parts of freehand drawings. Click and drag over the areas you want to erase.

Shapes

indiPDF supports several shape types:

  • Rectangle: Click and drag to draw rectangles
  • Circle: Click and drag to draw circles/ellipses
  • Line: Click and drag to draw straight lines
  • Arrow: Click and drag to draw arrows

For shapes, you can choose between solid (filled) and outline styles using the fill style selector in the toolbar.

↑ Go to Top



Signatures

Create and apply digital signatures to your documents.

Creating a Signature

  1. Select the Signature tool from the toolbar
  2. In the signature dialog, draw your signature using your mouse or trackpad
  3. Click Save Signature to save it for future use
  4. Click anywhere on the document to place the signature

Using Saved Signatures

Your signatures are saved automatically. When you select the Signature tool, you can choose from your previously saved signatures or create a new one.

Managing Signatures

In the signature dialog, you can delete signatures you no longer need by clicking the delete button next to each saved signature.

↑ Go to Top



Images and Stamps

Adding Images

  1. Select the Image tool from the toolbar
  2. Click where you want to place the image
  3. Select an image file from your computer
  4. The image will be inserted at the clicked location

Resizing Images

Click on an inserted image and drag the corners to resize it. The aspect ratio is maintained.

↑ Go to Top



Form Filling

indiPDF can fill out interactive PDF forms.

Filling Form Fields

  • Text fields: Click and type to enter text
  • Checkboxes: Click to check or uncheck
  • Radio buttons: Click to select an option
  • Dropdown menus: Click and select from the list

Calculated Fields

Some forms have calculated fields (like totals). indiPDF automatically calculates these values as you fill in the form.

↑ Go to Top



Page Management

Rotating Pages

  • Press Ctrl+R to rotate the current page 90° clockwise
  • Or use View → Rotate Page

Rotations are saved when you save the document.

Reordering Pages

  1. Open the sidebar (F9) to see page thumbnails
  2. Drag and drop thumbnails to reorder pages

Deleting Pages

  1. Right-click on a page thumbnail in the sidebar
  2. Select Delete Page

Adding Pages from Another PDF

  1. With a document open, click Add PDF in the toolbar
  2. Select one or more PDF files to add
  3. The pages will be appended to your current document

↑ Go to Top



Splitting and Merging PDFs

Merging PDFs

  1. Click Merge in the toolbar or select File → Merge PDFs
  2. Add the PDF files you want to combine
  3. Drag to reorder them if needed
  4. Click Merge to create a new combined document

Splitting PDFs

  1. Click Split in the toolbar
  2. Choose how to split:
    • Extract pages: Select specific pages to extract
    • Split by range: Define page ranges
  3. Choose where to save the extracted pages

↑ Go to Top



Exporting

Export as Images

  1. Click Export in the toolbar or select File → Export
  2. Choose the format: PNG, JPEG, or WebP
  3. Select which pages to export
  4. Choose the resolution/quality
  5. Click Export and select a destination folder

↑ Go to Top



Printing

  1. Press Ctrl+P or select File → Print
  2. Choose your printer from the dropdown
  3. Set the number of copies
  4. Select which pages to print (all, current, or custom range)
  5. Click Print

All annotations will be included in the printed output.

↑ Go to Top



Document Properties

View and edit PDF metadata:

  1. Select File → Document Properties
  2. Edit the following fields:
    • Title
    • Author
    • Subject
  3. Click Save to apply changes

↑ Go to Top



Keyboard Shortcuts

Shortcut Action
Ctrl+O Open file
Ctrl+S Save
Ctrl+Shift+S Save As
Ctrl+P Print
Ctrl+W Close document
Ctrl+F Find/Search
Ctrl+G Find next
Ctrl+Shift+G Find previous
Ctrl+Z Undo
Ctrl+Shift+Z or Ctrl+Y Redo
Ctrl++ Zoom in
Ctrl+- Zoom out
Ctrl+0 Fit to width
Ctrl+R Rotate page
Ctrl+M Toggle comment tool
F9 Toggle sidebar
Delete Delete selected annotation

↑ Go to Top



Licensing

Free vs. Licensed

indiPDF is free to use with full functionality. However, unlicensed copies add a small watermark to saved documents. Purchasing a license removes this watermark.

Activating a License

  1. Select Help → License Key
  2. Enter your license key
  3. Click Activate

Your license is validated locally and stored securely. No internet connection is required after activation.

Purchasing a License

To purchase a license:

↑ Go to Top



Tips and Tricks

  • Multiple documents: Open multiple PDFs in tabs and switch between them easily
  • Clipboard history: The sidebar shows your recent clipboard items for easy re-use
  • Quick tool switching: After placing an annotation, you can quickly switch back to the Select tool by pressing Escape
  • Precise positioning: Zoom in for more precise annotation placement
  • Undo everything: Almost every action can be undone with Ctrl+Z
  • Theme support: indiPDF automatically follows your system’s light/dark theme preference

↑ Go to Top



Troubleshooting

PDF won’t open

  • Ensure the file is a valid PDF document
  • Check if the file is corrupted by trying to open it in another PDF viewer
  • Some encrypted PDFs may not be supported

Annotations not appearing

  • Make sure you’ve selected a tool before trying to annotate
  • Check that you’re clicking/dragging on the PDF page, not outside it

Changes not saved

  • Look for the asterisk (*) in the tab title indicating unsaved changes
  • Use Ctrl+S to save
  • For flattened annotations, use File → Save & Flatten

Need more help?

Visit our bug report page to report issues or request features.

↑ Go to Top