← All tools

PDF tools, explained

Yunyu Chengye is a browser-based set of PDF tools provided by Cixi Yunyulai Culture & Technology Co., Ltd. It organizes images into PDFs, edits PDF pages, compresses PDFs and verifies registered files with YunyuTrace.

What can I do with Yunyu Chengye?

Create an A4 PDF from images, automatically split long screenshots, replace or insert pages with images, reorder PDF pages, compress a PDF, and verify a registered file using its verification code.

Are my original files uploaded?

Image and PDF processing, previews and digest calculation run locally in your browser. Original file content is not uploaded. Registration sends file digests and necessary metadata; encrypted verification proofs are stored for later checks. Keep your own copies of original and generated files.

Which features are free?

Basic Images to PDF export and basic PDF page replacement are free. PDF compression, optional signing after compression and YunyuTrace verification are free. Custom watermarks, footer changes and scan conversion are paid export features, currently CNY 1.99 per export. Editing is not charged; exporting again after changes requires a new payment. There is no subscription or automatic renewal.

What are the file limits?

Images to PDF supports up to 100 images totaling 160 MB, up to 200 output pages and a 200 MB output file. PDF page replacement supports up to 200 pages and 200 MB. Compression accepts PDFs up to 100 MB; verification accepts files up to 200 MB. Device memory and file complexity can impose lower practical limits.

What does a successful verification prove?

A matching file digest means the file bytes match a registered version. Signature checks verify the origin and integrity of registration records. Available page proofs compare rendered pages under fixed rules. These checks do not establish whether the content is true, who authored it, or whether a seal is authentic.

Can I use English and Chinese documents?

Yes. Use the 中文 / English links on the home page to choose the interface language. Image and PDF processing does not require the document language to match the interface. The tools do not translate document content.

Do I need an account or installed software?

No account or installation is required. Use a modern browser and keep the editor open until the download finishes. Files from a closed session cannot be recovered from the service.