Edit PDF tools

What "edit" means here

OmniPDF overlays new content on top of existing PDF pages. It does not modify the underlying text, images or formatting. This is a deliberate choice: safe, browser-based editing is overlay-based. Real PDF editing — changing existing characters, reflowing paragraphs, removing images — requires substantial reconstruction of the PDF structure and is far more prone to breakage.

For the vast majority of edit tasks (annotating, signing, highlighting, adding notes, filling blank boxes, marking corrections), overlay is exactly what you want. For tasks that require deleting or changing the original text, use a dedicated PDF editor.

Common edit tasks

• Add a note or correction — Add Text to PDF places text at a specific position.
• Place a logo or stamp — Add Image to PDF.
• Draw boxes or lines — Add Shapes to PDF for rectangular form fields, dividers and diagrams.
• Highlight key text — Highlight PDF with adjustable colour and opacity.
• Mark a correction — Strike Through PDF.
• Underline a phrase — Underline PDF.
• Sign a document — Draw on PDF or Sign PDF.
• Freehand sketch — Draw on PDF.
• Leave review comments — Add Comments to PDF.
• Add a clickable link marker — Add Links to PDF.

Privacy

All edit tools run locally. Files never leave your device. Safe for signing contracts, annotating medical records and marking up internal documents.

Interaction with signatures

Editing a PDF invalidates any existing digital signature because the bytes of the file change. If you receive a signed document and need to add a note without invalidating the signature, use a PDF annotation tool (like a PDF reader's built-in comment feature) rather than re-saving the file. OmniPDF edit tools always re-save, so use them on unsigned documents or accept that the signature will break.