How HanOpen works
HanOpen is a static website with a conversion engine that runs inside your browser. The document you convert is not sent to a server. This page describes every step it goes through, and how to verify that claim yourself instead of taking it on trust.
From the selected file to a local result
Choose the original attachment on a tool page. Document conversion reads the selected bytes into a background worker, interprets HWP 5.0 records or HWPX package parts, and writes the requested output from a shared document model. It also records detected and emitted elements.
Use the download control to save the result through your browser. Results stay available in the current page until you clear them or leave. Closing the conversion worker releases its working memory; it does not upload the document or save the result on our server.
Inspect local processing yourself
Open the Network panel in browser developer tools before running a tool. Load the page, run its example, then inspect the methods and request payloads while a result is produced. You will see site assets and analytics requests. Conversion and the optional page renderer can download additional program files.
The selected document bytes and filenames should not appear in an upload request. A change in the request list alone does not establish a file upload. The saved output is produced locally; later emailing or uploading that output is a separate action under your control.
Conversion summaries and usage measurement
The document summary compares detected and emitted paragraphs, tables, images and notes. Use it to locate parts that need review. Matching counts do not measure visual similarity or establish that the content is correct.
Google Analytics receives a fixed tool identifier, output format, elapsed time and success or failure counts for document and utility use. A failed operation also records its stage, and a displayed viewer document records a viewer-open event. Document events can include table, image and note counts. Filenames, document text and free input are excluded. Analytics choices and the separate cookie-free Ahrefs page measurements are described in the privacy policy.
Browser requirements and verification
Conversion requires JavaScript and background workers; page previews also use WebAssembly. No separate program or extension is required. An organisation’s security settings can prevent these browser features from running.
Conversion, viewing and utility flows have been checked with Chromium, Firefox and WebKit engines on Windows. These checks do not establish support on every operating system or on actual Safari and iPhone devices. Large documents also depend on available device memory, so check a representative file before relying on a result.
Use the limit for the selected operation
Document conversion reads the input into memory and also needs space for parsed content and output. Its file-selection cap is normally 200 MB, or 100 MB when the browser reports low device memory. Being below the cap does not guarantee that a complex document fits in memory.
SMI input has a separate 20 MB limit. Page preview accepts files smaller than 5 MiB and applies additional object-count and time limits. ZIP filename repair reads the archive directory and validates compressed entries in slices instead of expanding the whole archive into one buffer. Read the limit and warning on the tool you are using; byte size alone does not predict processing time.
Protection and unreadable input
For HWP 5.0, file-header flags identify the password, distribution and DRM restrictions that this version refuses. HWPX is a different package: a section body that is not readable XML is also refused. That observation alone cannot distinguish every protected file from a damaged package.
HanOpen does not ask for a document password or remove protection. Retain the original and check the displayed error. Obtain a fresh download for a damaged attachment, or ask its author for an editable copy you are permitted to use. Changing an extension does not repair the file or remove a restriction.
Source code
HanOpen’s source repository is private. Each tool page describes the features provided and their limits. You can inspect network requests using the steps above to check whether a document is uploaded.
Repeat a check with a fictional example
The tool pages provide original example files. Run an example through the same controls used for your documents, inspect its result, and download the input when you want to repeat the check.
| Example | Inspect the result | Scope of the check |
|---|---|---|
| A short fictional meeting documentHWPX to DOCX ConverterDownload the example input | Compare the expected text and the HWPX table cells with the converted document. Read detected and emitted counts together with warnings. | This small example does not establish support for complex forms, protected files, every font or every office application. |
| Legacy Korean ZIP filenamesFix Broken Korean Filenames in ZIPDownload the example input | Compare the proposed Korean names, download the repaired ZIP, and inspect the extracted names and file contents. | Decoded names still need review. Already overwritten name bytes and damaged contents cannot be restored by changing filename encoding. |
| Two language tracks and blank timing cuesSMI to SRT ConverterDownload the example input | Choose a track and compare its lines and timecodes. A blank cue ends the previous subtitle; the final duration applies only when no later cue exists. | The example has no video or audio. Matching these timecodes does not establish synchronization with a real video. |
Generated-file checks, browser operation and visual inspection in an office application answer different questions. Our examples expose a small repeatable check; use your original as the reference for work that depends on specific document content or appearance.