How to merge, split and convert PDFs on your device
PDF files pile up fast — you need to combine a contract with its attachments, pull out a single page to share, or turn a scanned photo into a proper document. This guide walks you through the four most common PDF tasks and shows you how to handle all of them privately on your own device, without uploading anything to a third-party website.
Combine multiple PDFs into one file
Merging PDFs is the most frequent request in any office or study routine — assembling invoices, stitching together a multi-part report, or bundling a CV with cover letter and portfolio. With Carbide's Merge PDF tool you pick the files you want, drag them into the order you need, and export a single clean PDF in seconds. Because the tool runs entirely on your device, none of your documents are sent anywhere. No account required, no upload limit, and it works just as well on an aeroplane as it does on fast Wi-Fi.
Extract pages or split a PDF into separate files
Sometimes you only need one chapter out of a fifty-page manual, or you want to send a client a single slide rather than the whole deck. Carbide's Split PDF tool lets you enter a page range — say pages 3 to 7 — and export just those pages as a new PDF. You can also split every page into its own file if you need to restructure a document from scratch. The operation is instant for typical file sizes and, again, completely offline — useful when you are working with sensitive contracts or medical records.
Turn images into a PDF (and back again)
Need to submit a scanned form or create a photo album as a PDF? Carbide's Image to PDF tool lets you pick one or more photos from your gallery, choose a page layout, and export a properly formatted PDF document. Going the other direction is just as easy: PDF to Image extracts each page as a high-quality image file, which is handy for pulling a chart out of a report or previewing a page without a PDF reader. Both tools are free and do their work locally, so photos of your passport or bank statements never leave your phone.
Why on-device PDF tools protect your privacy
Most free PDF websites work by uploading your file to a remote server, processing it there, and then letting you download the result. Your document sits on someone else's infrastructure — even briefly — and you cannot verify what happens to it. Carbide takes the opposite approach: every PDF operation runs inside the app on your own hardware. There is no sign-in, no file storage in the cloud, and no network request involved. For documents that contain personal, financial or confidential information, keeping processing local is not just convenient — it is the only sensible choice.
Frequently asked questions
- Is Carbide's PDF tools really free?
- Yes. Merge PDF, Split PDF, Image to PDF and PDF to Image are all included in the free version of Carbide with no usage limits. An optional Remove Ads upgrade is available if you prefer an ad-free experience, but you never need to pay to use the PDF features.
- Do I need an internet connection to merge or split PDFs?
- No. All PDF processing in Carbide happens on your device. You can merge, split and convert PDFs completely offline — on a flight, in a basement, or anywhere else without a signal.
- What file size or page count limits apply?
- Carbide does not impose an artificial file size cap the way web tools do. The practical limit is your device's available memory. Very large files (several hundred pages or dozens of high-resolution images) may take a few extra seconds, but everyday documents process in under a second.
- Can I merge PDFs with images (JPG, PNG) in a single step?
- The cleanest workflow is to convert your images to PDF first using Image to PDF, then merge the resulting PDF with your other documents using Merge PDF. That two-step process gives you full control over page order and layout before the final merge.