Core PDF Tools

What is the best way to reduce a PDF file size for email?

The most effective way to reduce a PDF file size for email is to use a PDF compressor. Dockitt's Compress PDF tool re-optimises the internal structure of your file — removing redundant data and streamlining object streams — without visually altering the content. For text-heavy PDFs such as reports, contracts, and presentations, the size reduction is often significant. If your PDF contains many high-resolution images, the reduction may be smaller since image data is harder to compress without quality loss. Most email clients have a 10MB or 25MB attachment limit, and compressing your PDF before sending is the cleanest way to stay within those limits without splitting the document.

How do I combine multiple PDF files into one document?

Use the Merge PDF tool. Upload all the files you want to combine, arrange them in the correct order, and download the merged result. The tool preserves the content, formatting, fonts, and images of each individual file exactly as they are — merging only joins the pages together into a single document without altering anything inside each file. This is useful for combining a cover letter with a CV, assembling a report from multiple chapters, or consolidating scanned pages from different sources. If any of the files are password protected, you will need to unlock them first using the Unlock PDF tool before merging.

What is the difference between splitting and extracting pages from a PDF?

Split PDF lets you define a consecutive page range to extract as a new document — for example, pages 1 through 5. Extract PDF Pages lets you specify individual page numbers in any order, which is useful when the pages you need are not consecutive. For example, if you need pages 2, 7, and 14 from a 30-page document, use Extract PDF Pages. If you need the first 10 pages of a document, use Split PDF. Both operations are non-destructive — they create new files without modifying the original.

Can I rotate only specific pages in a PDF, not the entire document?

The Rotate PDF tool currently rotates all pages in a document by the same angle. If you need to rotate only specific pages, the workaround is to split the document into sections using the Split PDF tool, rotate the relevant section, then merge everything back together using the Merge PDF tool. This takes a few extra steps but gives you full control over which pages are rotated and by how much.

Will compressing a PDF affect the quality of images inside it?

Dockitt's Compress PDF tool works by optimising the PDF's internal structure — removing redundant metadata, streamlining object references, and cleaning up file overhead — rather than re-compressing the images themselves. This means that for most PDFs, image quality is not affected. The approach works best on text-heavy documents. For PDFs where the majority of the file size comes from embedded high-resolution images, the compression gains will be more modest because the images themselves are not touched.

Is there a file size limit for these PDF tools?

Files up to 4.5MB can be processed directly. This limit comes from the Vercel serverless function payload limit for tools that require server-side processing. For tools that run entirely in the browser — such as Merge PDF, Split PDF, Rotate PDF, and Compress PDF — the practical limit is higher and depends on your device's available memory. If your file exceeds the limit for a server-side tool, try compressing it first to bring it under the threshold, or split it into smaller sections.