Free Tier Restrictions
Smallpdf's free tier is the most restrictive among major PDF services: 2 tasks per day and a 15 MB file size limit. This makes it impractical for anyone with moderate PDF processing needs. LocalPDF imposes no task limit and no file size restriction on any operation.
Privacy
Like all major PDF tool services, Smallpdf uploads your files to their servers for processing. They are based in Switzerland and comply with Swiss and EU privacy laws. However, any server-based service involves trusting a third party with your document content. LocalPDF's browser-based processing eliminates this trust requirement entirely.
Cloud Integration vs Privacy
Smallpdf integrates with Google Drive, Dropbox, and OneDrive, which is convenient for users who already store documents in the cloud. LocalPDF does not offer cloud integration by design, since cloud integration implies uploading your documents to external services, which conflicts with the privacy-first approach.
Tool Coverage
Smallpdf covers core PDF operations well. LocalPDF additionally offers Flatten PDF, Repair PDF, and Compare PDF, tools that Smallpdf does not provide. For the vast majority of everyday PDF tasks, both services have everything needed.
Verdict
Smallpdf suits users who need cloud storage integration and do not mind the 2-task daily limit for occasional use. LocalPDF suits users who need unlimited free access, work with sensitive documents, or process more than a couple of PDFs per day.