Merge 10 or more PDF files into one

More than 5 files? Merge them in groups of up to 5, then merge the group results.

Drag & drop PDF files here

Free: up to 5 files, 20MB total

How batching works

The free merge takes up to 5 files at a time. When you have more, merge them in groups of up to 5, then merge the group results. Merges are unlimited, so batching costs only a few extra clicks.

Batch plans for 10, 15 and 20 files

10 files: merge files 1 to 5 into batch-1.pdf and files 6 to 10 into batch-2.pdf, then merge batch-1.pdf and batch-2.pdf. That is 3 merges (2 + 1).
15 files: three merges of 5 files give batch-1.pdf, batch-2.pdf and batch-3.pdf, then one merge of those 3 results. That is 4 merges (3 + 1).
20 files: four merges of 5 files, then one merge of those 4 results. That is 5 merges (4 + 1).

The pattern is one merge per group of 5, plus one final merge of the group results. Keep the batches in order, so the last merge reads batch-1, batch-2, batch-3.

Name the intermediate files

Name each group result so you can tell them apart: batch-1.pdf for files 1 to 5, batch-2.pdf for files 6 to 10, and so on. Delete them when you have the final file. Your original files are never changed.

Batching does not get around the 20MB limit

The 20MB limit applies to the files going into each merge. The last merge takes the group results, and merging does not compress, so those results add up to roughly the size of all your original files together. On the free version the final total has to fit in 20MB too.

Example: 10 files of 1.5MB each are 15MB in total. Each group is 7.5MB, and the final merge takes 15MB, which fits. Ten files of 2.5MB each are 25MB in total. Each group is 12.5MB and merges fine, but the final merge would take 25MB, so the Pro prompt appears instead of merging. Here is what to do with large files.

When Pro helps

Pro removes the file-count and size limits, so a single merge can take all your files at once and you can skip the batching.

What this does not do

It joins whole files only. It does not split files, reorder or delete pages inside a file, or compress anything, and it does not clean up your intermediate files for you.

More about merging PDFs

Free, with an optional Pro unlock

Pro is Hexloom Pro, $29 a year or $4 a month, one subscription for every Hexloom tool. It removes the 5 file and 20MB limits. There is no account: Pro unlocks the browser you subscribe in, and the confirmation page has a link to restore it elsewhere.