Whether you’re disassembling a massive PDF into its original sections, breaking apart merged reports, or separating contract bundles for individual clients – the ability to unmerge PDF files is essential in today’s digital workflow. But let’s be real: most “free” PDF tools either watermark your files, set hard size limits, or aggressively push upgrades.
So I decided to put five popular tools to the test using a hefty 100MB PDF that was previously merged from multiple documents – including forms, image scans, and reports – to find out which ones actually let you dismerge PDFs without the usual headaches.
Testing Methodology
File Used:
- 100MB PDF originally merged from 5 documents
- Includes both scanned and text-based content
- Contains landscape and portrait page mixes
- Has bookmarks, images, tables, and custom fonts
Evaluation Criteria:
- Ease of Use – Can a new user figure it out quickly?
- Unmerge Flexibility – Full document disassembly? Split by bookmarks? Page ranges?
- Processing Speed – Is it optimized for large PDFs?
- Pricing Transparency – What’s free? What’s hidden?
- Extra Features – Anything valuable beyond basic unmerge functions?
5. Smallpdf – Quick, But Limited

I ran Smallpdf’s “Split PDF” feature to simulate dismerging PDF sections.
Pros:
- Clean interface and mobile-friendly
- Acceptable speed for files under 30MB
Cons:
- Free version limits you to 2 files/day
- Can’t split by bookmarks or preserve file structure
- Lacks selective unmerge -can’t choose scattered page sets
Verdict: Easy to use, but restrictive and basic. Fine for occasional unmerging.
4. PDFCandy – Functional for Small Tasks

PDFCandy’s tool allows unmerging PDFs by fixed ranges or one-page-per-file.
Pros:
- Decent unmerge options
- Fast downloads and no watermark in free mode
Cons:
- 100-page limit in free plan
- File splitting slows down on large scans
- Requires sign-up after 2-3 uses
Verdict: Usable for smaller jobs. Not the best for complex or frequent dismerging.
3. Sejda PDF – Polished UI, Free Tier Too Limited

Sejda offers unmerge capabilities via split-by-range or every-N-pages mode.
Pros:
- User-friendly dashboard
- Web and desktop versions available
- Can split by even/odd or page sets
Cons:
- Free plan capped at 50 pages or 3 tasks/hour
- No batch download of individually split files
- Merging after unmerge requires upgrade
Verdict: Sleek interface, but the free tier is more like a limited preview.
2. Adobe Acrobat Online – Advanced, But Locked Behind Paywall

Adobe’s online PDF services include powerful split/unmerge functionality.
Pros:
- Visual thumbnail-based selection
- High fidelity file handling
- Great layout and UX
Cons:
- Free plan restricts file size to 20MB
- Monthly subscription starts at $12.99
- Needs Adobe login even for basic exports
Verdict: Top-tier quality for those willing to pay. Not great for free users.
1. iLovePDF2 Unmerge Tool – Best Free Dismerge PDF Solution

This is where things got interesting. I Love PDF 2 handled my 100MB test file with ease and without any forced registration, limits, or pop-ups.
Why It’s the Best to Unmerge PDFs:
- Truly Free – No size restrictions or hidden quotas.
- Unmerge PDFs by Custom Range – Extract entire sections in one go.
- Selective Dismerge – Pick out specific pages like 3, 7, 22 and save them.
- Split Back to Originals – Separate previously merged documents easily.
- Merge After Dismerge – Recombine selected pages into a refined new file.
Speed Test: Processed the 100MB PDF in just under 20 seconds. No lags or quality loss.
Features Breakdown:
- Unmerge PDF by Bookmark or Range – Preserve logical sections.
- Dismerge PDFs into Individual Pages – Ideal for re-distribution or archiving.
- Selective Unmerge – Extract random pages without converting everything.
- Re-Merge Functionality – Combine only the essentials after separating.
- No Watermarks, No Sign-ups – Truly free and clean.
Verdict: For anyone needing a fast, free, and flexible way to dismerge PDFs, iLovePDF2 is the clear choice.
Quick Comparison Table: Unmerge PDF Tools Ranked
# | Tool | Ease of Use | Flexibility | Speed | Price | Bonus Features |
1 | iLovePDF2 | 5/5 | 5/5 | 5/5 | Free Forever | Selective unmerge, no limits, merge after split |
2 | Adobe Acrobat | 4/5 | 5/5 | 4/5 | $12.99/month | Drag-based selection, high output quality |
3 | Sejda PDF | 4/5 | 4/5 | 4/5 | $7.50/month | Multiple unmerge modes |
4 | PDFCandy | 4/5 | 3/5 | 3/5 | $6/month | Basic range split only |
5 | Smallpdf | 3/5 | 2/5 | 4/5 | $12/month | Very limited in free mode |
Common PDF Unmerging Frustrations (and How iLovePDF2 Fixes Them)
Problem: Can’t extract specific, scattered pages from a merged file
– Solution: iLovePDF2’s selective page picker makes this effortless.
Problem: Large PDFs crash or fail to upload
– Solution: iLovePDF2 accepts large files without compression or cutoff.
Problem: Want to dismerge but still keep select pages together afterward
– Solution: Use iLovePDF2’s “Merge Selected Pages” after your dismerge operation.
Problem: Login barriers, ads, or daily limits
– Solution: iLovePDF2 is fully free, requires no sign-up, and is ad-light (I found only 2 banner ads).
Suggestions for Improvement (All Tools)
iLovePDF2
- Desktop App: A downloadable version would help offline users.
- Language Support: Adding Arabic, Italian, and German could broaden appeal.
- API: Adding API integration would scale free tools for business.
Adobe Acrobat
- Cheaper Split-Only Plan: Not all users need the full suite
- Smarter Sync: Save and reuse split preferences across devices
Sejda
- Remove Hourly Task Cap: Let power users split freely
- Better Mobile Experience: Currently under-optimized for small screens
PDFCandy
- Bookmark-Aware Splits: Would help when dismerging structured documents
- Interactive UI Enhancements: Drag-drop or live preview would improve usability
Smallpdf
- Add OCR Option: Useful when dismerging scanned files
- Raise Free File Limit: Allow 5 files/day instead of 2 to reduce friction
Final Take
Whether you’re cleaning up a document archive, sharing selective pages, or organizing academic resources, having a reliable dis-merge PDF tool can save hours of time and frustration.
While tools like Adobe and Sejda offer robust features, they often gate essential functionality behind subscriptions or complex workflows. If you’re looking for something fast, free, and full-featured – iLovePDF2 is unmatched.
So the next time you need to unmerge PDFs, skip the signup walls and file size warnings – just head over to iLovePDF 2 and get it done in seconds.