About

Professional environments frequently require the consolidation of fragmented documents into a single, cohesive file. Whether compiling financial reports, legal contracts, or academic portfolios, the integrity and order of these documents are paramount. This tool addresses the critical need for data privacy by executing the entire merge operation locally within the browser context. Unlike server-side solutions, your sensitive files are never transmitted over the network, ensuring zero exposure to third-party storage or interception risks.

Accuracy in document sequencing is achieved through a binary-level merging process. The tool parses the raw ArrayBuffer of each file, extracting page dictionaries and content streams without rasterization. This preservation of vector data ensures that the output quality remains identical to the source. The architecture handles complex document structures, efficiently managing cross-reference tables to produce a compliant PDF standard file ready for immediate distribution or archival.

Formulas

When merging documents, the estimated final file size S_total is roughly the summation of individual input file sizes, plus a structural overhead δ for the new cross-reference table and catalog dictionary. Note that this assumes no font subset duplication removal.

S_total ≈ n∑i=1 S_i + δ

Where S_i represents the binary size of the i-th PDF file in bytes, and δ represents the overhead (typically 2 - 5 KB). If efficient object streams are used, S_total may be slightly smaller than the raw sum due to shared resource optimization.

Reference Data

Format Standard	Dimensions (mm)	Dimensions (in)	Points (72 DPI)	Typical Usage
A4	210 × 297	8.27 × 11.69	595 × 842	International Standard
Letter	215.9 × 279.4	8.5 × 11.0	612 × 792	North America Standard
Legal	215.9 × 355.6	8.5 × 14.0	612 × 1008	Legal Contracts
Tabloid	279.4 × 431.8	11.0 × 17.0	792 × 1224	Newspapers / Ledgers
A3	297 × 420	11.69 × 16.54	842 × 1191	Drawings / Diagrams
A5	148 × 210	5.83 × 8.27	420 × 595	Booklets / Pamphlets
Executive	184.1 × 266.7	7.25 × 10.5	522 × 756	Stationery
B5 (ISO)	176 × 250	6.93 × 9.84	498 × 708	Books

Frequently Asked Questions

Yes. This tool operates entirely client-side using WebAssembly and JavaScript. Your files are loaded into your browser's memory (RAM), processed locally, and the final file is generated on your device. No data is ever sent to a remote server, eliminating the risk of interception or unauthorized storage.

Browser-based tools are constrained by the available memory allocated to the tab. Merging very large files (e.g., exceeding 500 MB combined) may trigger a memory limit exception. For optimal performance, ensure you have sufficient RAM available and try closing other tabs if processing high-resolution documents.

Generally, merging flattens the document structure. While form fields may be preserved visually, their interactive properties (AcroForms) are often reset or removed to prevent conflict between fields with identical names across different files. Digital signatures are invariably invalidated because the file hash changes upon modification.

No. The parser requires access to the unencrypted content stream to extract pages. You must decrypt the PDF (remove the password) using a PDF unlock utility before attempting to merge it with other documents.

No. The tool performs a "page copy" operation. It takes the existing objects (images, fonts, vector paths) from the source file and places references to them in the new file. It does not re-encode or compress images, preserving 100% of the original quality.