Tinkr
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Student·Live· Merged in your browser

Merge PDF

Combine multiple PDFs into a single file. Drag, drop, reorder, click merge — done. Files never leave your machine; everything runs in your browser via pdf-lib.

Drop PDFs here, or click to browse
Add as many as you like. Reorder them below before merging.
Merged entirely in your browser

Your PDFs are read into memory and combined locally with pdf-lib. Nothing is uploaded to a server. Safe for confidential contracts, tax documents, and unreleased work.

Frequently asked questions

Are my PDFs uploaded to a server?
No. The PDFs are read into your browser's memory and combined locally using pdf-lib (a pure-JavaScript PDF library). Nothing is sent to a server, no account is needed, and you can disconnect from the internet and the merge still works. Safe for tax documents, contracts, and other confidential files.
How many PDFs can I merge at once?
There's no hard limit, but combined size practically maxes out around 50–100 MB depending on your machine's memory. Browsers cap how much memory a tab can use, and very large merges can hit that wall. For huge document sets, merge in batches.
Can I reorder the PDFs before merging?
Yes. After dropping the files, use the up/down arrows next to each entry to reorder them. The final merged.pdf concatenates pages in the order shown in the list — first file's pages first, last file's pages last.
Does it work on password-protected PDFs?
Not yet. If a PDF is encrypted with a real user password, the merge will fail with an error. For now, decrypt the PDF first (e.g., open it in a PDF reader, choose 'Print' → 'Save as PDF'), then merge the unprotected version.
Will bookmarks, form fields, and annotations survive?
Page content, images, and most annotations are preserved. Form fields and outlines (bookmarks) may not transfer cleanly because pdf-lib's copyPages doesn't propagate the document-level outline tree. For form-heavy PDFs, merge with caution and verify the output.
Is the merged PDF the same quality as the originals?
Yes. Merging copies the original page objects byte-for-byte into a new container — there's no re-rendering or re-compression. Pages keep their original resolution, fonts, and vector graphics. For lossless concatenation, this is the right tool.
What browsers are supported?
Modern Chrome, Edge, Firefox, and Safari (last two major versions). The tool relies on standard Web APIs (File, Blob, ArrayBuffer) plus pdf-lib, which targets the same baseline. Internet Explorer and very old mobile browsers are not supported.
Why not use iLovePDF or Smallpdf?
Those tools upload your PDF to their servers. That's fine for non-sensitive content but problematic for legal documents, signed contracts, ID scans, or anything covered by GDPR/HIPAA. Tinkr's merge runs entirely in your browser, so your data never leaves your device.

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