How Many PDFs Can I Merge at Once?

There's no fixed limit on the number of files you can add to Merge PDF — you can add as many PDFs as you want to combine into one document. The one real constraint is size: each individual file can be up to 100MB, and because merging processes everything in your browser rather than on a server, adding a very large number of sizable files will use more of your device's memory and take longer to process. For most everyday merges — combining a handful of documents — this isn't something you'll notice.