How to merge PDFs
- Drop your PDFs on the page, or choose them. You can add images too; they become pages.
- Drag the files into the order you want, or use the arrows. Each shows a preview of its first page and its page count.
- Click “Merge and download”.
Pages keep their original size, orientation and quality. Nothing is re-compressed.
Unlimited and private
Many PDF websites allow only two merges a day for free, cap file sizes, and upload everything to their servers. SmallKits merges on your device with no daily limit and no file-size cap beyond what your device can handle. Your files are never uploaded.
Forms and fields
If two PDFs have form fields with the same names, merging them can make the fields copy each other. “Flatten form fields” (on by default) turns filled-in fields into ordinary text before merging, so every page keeps exactly what was typed.
Password-protected files
PDFs locked with a password are skipped and marked in the list. Open them in your PDF viewer with the password, print or save a copy without the password, and add that copy.
Common uses
- Combining an invoice, a delivery note and a signed purchase order to send to a client’s accounts team.
- Putting together a job or visa application from several scanned documents.
- Joining monthly statements into one file for your accountant.
What next
Too big to email? Compress the merged PDF. Need to remove a page? Use Split PDF. Need to sign it? Use Fill and sign PDF.
A worked example
An accounts team asks a supplier to send “one PDF per payment” containing the invoice, the signed delivery note and the purchase order. The supplier drops the three PDFs on the page, drags the invoice to the top, adds a photo of the stamped delivery note straight from their phone, and clicks “Merge and download”. The result is one file named after the invoice, with every page at its original quality, ready to attach to an email.
Ordering tips
- Put the document the reader needs first at the top, usually the invoice, cover letter or application form.
- Keep related pages together, such as a contract and its schedules.
- Check page counts in the list to make sure nothing is missing before you merge.
- Use the arrows instead of dragging on a phone; they are easier with a thumb.
Mixed page sizes
Merging an A4 report with a US Letter form or a landscape spreadsheet works fine: each page keeps its own size and orientation, exactly as in the original files. If you need everything on the same paper size, print the merged PDF with “fit to page”.
Why on-device matters
Merged files are often bundles of personal and financial documents: applications, statements, IDs and contracts. Uploading them to a free website means trusting a stranger’s server. With SmallKits, the files are read and combined in your browser, and you can disconnect from the internet after the page loads to prove it.
Problems and fixes
- A file is marked “Password protected”: save an unlocked copy and add it again.
- A file is “damaged or not a PDF”: open it in your PDF viewer and print it to a new PDF, then add that.
- The merged file is too large: use Compress PDF.
- Form answers copy between files: keep “Flatten form fields” ticked.
Terms explained
- Flatten
- Turn form fields into ordinary text so they can no longer be edited.
- Page count
- The number of pages in each file, shown in the list before you merge.
Merging on a phone
On Android and iPhone, tap “Choose files” to pick PDFs from your downloads, email attachments or cloud storage such as Google Drive or iCloud. Use the arrows to put them in order, then tap “Merge and download”. On phones with a Share button, you can send the merged file straight to WhatsApp or email.
Related free tools
- Free split PDF tool: to take pages out again.
- Free compress PDF tool: to make the merged file smaller for email.
- Free images to PDF converter: to turn photos into a PDF first.
One more tip
Give the merged file a clear name before you send it, such as the invoice number and your company name. Accounts teams receive hundreds of attachments, and a good file name helps yours get processed first.
Updated 2026-10-29