PDF Editor

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PDF Editor

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Edit, merge, split, compress, and watermark PDFs online. Fast, secure, and free.

or drag and drop

📋 PDF Editor Features

✓ Merge multiple PDFs into one
✓ Extract specific pages from a PDF
✓ Compress PDF to reduce file size
✓ Add watermarks to all pages
✓ Fast client-side processing
✓ No file upload to servers

AI Insight

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📄 PDF Editor — Complete Guide

1993

Year Adobe invented the PDF format

Up to 70%

Typical PDF compression reduction

PDF/A

ISO archival standard for long-term storage

2.5 trillion

Estimated PDFs in existence worldwide

PDF Operations Reference

Operation	What It Does	Typical Use	Output
Merge	Combine multiple PDFs into one	Combining reports, chapters	Single PDF
Split	Separate PDF into individual pages or ranges	Extracting pages, booklets	Multiple PDFs
Compress	Reduce file size by optimizing images/fonts	Email attachments, web upload	Smaller PDF
Rotate	Turn pages 90°, 180°, or 270°	Fixing scanned document orientation	Rotated PDF
Watermark	Add text or image overlay to all pages	Copyright, draft marking, branding	Watermarked PDF
Reorder	Rearrange page order	Reorganizing documents	Reordered PDF
Unlock	Remove password protection (if you have it)	Editing protected files you own	Unlocked PDF
PDF to image	Convert pages to PNG/JPG	Sharing non-editable content	Image files

Frequently Asked Questions

Is it safe to upload my PDF to an online editor?›

Our PDF editor processes files locally in your browser using JavaScript — your files are never uploaded to a server. For sensitive documents (contracts, tax forms, medical records), always verify the tool processes files client-side. Avoid browser-based tools that require server upload for highly confidential documents.

Why is my PDF so large and how do I compress it?›

PDFs grow large due to: high-resolution embedded images (most common cause), embedded fonts (can be subsetted), uncompressed streams, and metadata. Compression works by downsampling images (300 DPI → 150 DPI for screen viewing), subsetting fonts (only embed used characters), and applying flate compression. Scanned PDFs can often compress 50–70%; text-only PDFs compress less (10–30%).

What is the difference between merging and combining PDFs?›

Merging = combining full PDFs in order. Combining = selecting specific pages from multiple PDFs. Both produce a single output PDF. Merging is faster; combining gives you page-level control. For a book chapter from one PDF and an appendix from another, use combine (select pages); to bind an invoice + receipt + contract, use merge.

Can I edit text inside a PDF?›

True text editing requires a desktop PDF editor (Adobe Acrobat, Foxit, PDFelement). Web tools can add text annotations (floating text boxes) on top of existing content. Scanned PDFs contain images of text — to make them editable, you need OCR (Optical Character Recognition) to convert the image into selectable text.

What is PDF/A and when should I use it?›

PDF/A (ISO 19005) is an archival subset of PDF designed for long-term preservation. It embeds all fonts, prohibits encryption, disallows external references, and requires device-independent color. Use PDF/A for: legal documents, government submissions, medical records, anything requiring 10+ year preservation. Many courts and agencies require PDF/A-1 or PDF/A-2 compliance.

How do I reduce a PDF file size for email?›

Most email servers limit attachments to 10–25 MB. Steps to reduce: (1) Compress images to 150 DPI screen quality. (2) Subset embedded fonts. (3) Remove hidden layers and metadata. (4) If still large, split into smaller files and zip. For files over 10 MB, consider sharing via Google Drive or Dropbox link instead of attachment.

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PDF Editor

Edit PDF files online for free. Add text, annotations, signatures, and merge or split PDF documents. No installation required. Fast, secure, and browser-based.

PDF Editor — Answer & Method

Edit PDFs: merge, split, compress, add watermarks, and download results. Fast, secure, client-side processing.

Formula: PDF Operations

PDF Merge: Combine page arrays | PDF Split: Extract page range | Compress: Optimize

P = PDF Files

Example Calculation

Combine 3 PDF files into one document.

Important limitation

Check the result against your specific circumstances before making a decision.

Key Facts

PDF editing can be done client-side using pdf-lib library.

Sources & Validation

PDF specification (ISO 32000)

Deterministic: YesAI-Generated Numbers: NoVerified: 2026-02-12

Want to learn more? Browse our calculation guides and tutorials →