Document processing
Local browser processing
Current supported tool workflows do not intentionally upload document contents to Kukureku servers for processing.
Trust Center
What Kukureku does with your files — and how to verify it
Kukureku's current PDF tools are designed to process supported files locally in your browser. This page documents the current processing model, practical limits, analytics disclosure, and verification paths in one place.
Account requirement
No account required
The current launch tools can be used without creating a Kukureku account.
Website analytics
Vercel Web Analytics
Page-view analytics are separate from document processing and are disclosed in the Privacy Policy.
Current tool processing matrix
The table below reflects the current public launch. Browser memory, document complexity, and unsupported file features can still affect whether a particular file completes successfully.
| Tool | Input | Current limit | Processing | Notes |
|---|---|---|---|---|
| Merge PDF | 25 MB per PDF | In browser | Combines pages locally in the browser. | |
| Split PDF | 25 MB | In browser | Extracts selected pages locally. | |
| Compress PDF | 25 MB | In browser | Optimizes locally; reduction depends on the source file. | |
| PDF to Word | 25 MB | In browser | Best for selectable-text PDFs; scanned pages need OCR. | |
| Word to PDF | DOCX | 25 MB | In browser | Supports readable text, headings, lists, and basic tables. |
| JPG to PDF | JPG / PNG | Browser memory | In browser | Embeds selected images into a PDF locally. |
| PDF to JPG | 25 MB | In browser | Renders selected pages as JPG images locally. | |
| Organize PDF | 25 MB | In browser | Reorders, rotates, moves, and removes pages locally. | |
| Watermark PDF | 25 MB | In browser | Adds text or image watermarks locally. | |
| Unlock PDF | Protected PDF | 25 MB | In browser | Uses the correct password locally for files you are authorized to modify. |
Verify the no-upload workflow yourself
You do not have to rely only on a privacy statement. Open your browser's Network panel, clear the request list, select a test document, and run a tool. The important check is whether the file contents are transmitted in a file-sized upload request to a conversion endpoint.
Follow the verification guide →Public implementation evidence
Kukureku's source repository is publicly viewable on GitHub. That provides another way for technical users to inspect the current browser-side implementation and follow changes over time.
View the public GitHub repository →What local processing does not mean
It does not mean the website makes zero network requests. The page, scripts, fonts, hosting infrastructure, and website analytics can make ordinary requests while the site is open.
It does not mean every possible document is supported. Very large, damaged, encrypted, scanned, or unusually complex files can exceed the capabilities of the current browser-based engines.
It also does not replace your own device security. Downloaded results remain your responsibility once they are saved to your computer or phone.