合并 PDF 文件
将多个 PDF 文件合并为一个文档。拖拽页面卡片按您的偏好自由排序。
选择 PDF 文件
或将 PDF 文件拖拽至此处
文档流重构与合并：PDF 拼接技术深度解析
Merging PDF files is more than just placing pages side by side. It requires parsing the underlying document structure, managing the page tree references, and compiling resources such as fonts and images into a single cohesive binary structure.
The PDF Document Structure & Page Trees
At the code level, a PDF is organized as a directed graph of objects. The root of this graph is the Catalog, which links to a Pages tree. When merging two or more PDFs, a compiler must walk these page trees, copy the individual Page objects, resolve conflicts in font dictionaries or color spaces, and construct a new, unified page index. Simply concatenating the files would result in an invalid document.
The Security Advantage of Local In-Browser Merging
Traditional web utilities require you to upload your files to their servers, exposing sensitive business contracts or personal documents to external storage. DocumentAlter utilizes advanced JavaScript libraries (such as pdf-lib) to merge files directly inside your browser sandbox. The file binary is compiled directly in your device's memory (RAM) and never transmitted over the network, providing complete data privacy.
如何合并 PDF 文件（分步操作指南）
Import Target PDF Documents
Select or drag and drop the PDF files you want to combine. These are loaded directly into browser memory.
Arrange Compilation Order
Rearrange the documents in the compilation queue. The merging process reads them sequentially from first to last.
Compile Page Trees
Run the merger to rewrite the cross-reference tables and save the consolidated document locally.
常见问题解答
将需要合并的 PDF 文件拖拽至 DocumentAlter 的 "合并 PDF" 工具中，拖动调整页面顺序，点击 "合并 PDF" 即可在浏览器中瞬间完成合并。
完全没有。因为所有运算均在您本机的浏览器内存（RAM）中执行，不经过任何云端服务器，因此不受任何文件大小或带宽限制。
绝对安全。DocumentAlter 完全在客户端运行，您的文件绝不会离开您的设备或上传至任何远程服务器。