Supporting tool · Live
Edit the PDF without sending the file away.
Typical online editors ask for an upload. VixPDF opens the document in the browser, edits it there, and only then writes a file the person can keep. We designed and shipped it.
The gap
Editing a contract, a form or a scan usually means handing the file to someone else's server. For a lot of work that is the wrong size of system. The job is local. The risk is not.
VixPDF exists because that path was the default, not because the studio needed another product to sell. It is a supporting tool. A later client build may reuse the thinking. The client is not buying VixPDF.
Local first
There is no document-upload endpoint. PDF bytes, extracted text, edits, images and signatures stay in browser memory. Closing the tab ends the session.
The public site is a static application. The only application endpoint is a content-free telemetry post with an allowlist of technical codes. Optional product analytics wait for consent and never include filenames, text, edits or file bytes.
Fonts, rendering and export
A PDF may embed a full font, a subset, or only outlines. Substituting a generic face at the same point size changes width and baseline. The editor keeps a same-origin catalog of 19 redistributable families and fetches only the face that matches.
Faithful export is a verified step, not a button that hopes. The rewritten bytes are reopened locally. Edited text must extract correctly, and the painted band is compared with the editor preview. If that cannot be guaranteed, the person is offered a disclosed visual copy. A corrupt file is not downloaded quietly.
- 01 Detect Text fields from the page
- 02 Match a face Catalog, then a local font if needed
- 03 Rewrite Only the supported source
- 04 Verify Extract and compare the band
- 05 Download The same bytes that passed
Desktop and mobile
The desktop path is a workspace with pages, fields and a property panel. On a phone the same job is a short transaction. The first tap selects a field, the second opens it, Done commits the draft and Cancel restores the field exactly.
A move handle is separate from the field body so the person can still pan the page. That was built and checked on mobile Chrome against the live site, not only on a wide desktop window.
Privacy and security
Every PDF and font is treated as hostile input. Metadata and the PDF signature are checked before parsing. Resource limits cover page geometry, canvas size, operators and analysis time so a pathological file cannot take the tab down without warning.
Signed, scripted and some form-based documents run only with explicit limitations. What the product will not do is as much of the design as what it will.
How it was built
The work followed the same sequence as a client system. Diagnose the constraint. Keep the file local. Make export a verified state, not a hope. Then close the mobile path so the tool is complete on a phone.
English and Brazilian Portuguese ship together. Releases go through type, lint, unit, privacy, telemetry-allowlist and browser gates. Production is an immutable image of a known commit.
What we can show
The product is live at vixpdf.com. The interface is English and Brazilian Portuguese. Desktop and mobile Chrome were used as the public check, against a synthetic adversarial corpus. We do not publish how many PDFs were opened or exported.
The evidence is the running editor, the privacy pages, and the fact that a faithful export can fail closed.
What you are not buying
Not VixPDF, and not a package called “PDF”. You are buying judgment around a process that is the wrong size for the job. If a supporting tool we have already shipped shortens that work, we reuse it. If it would distort the brief, we build what the business actually needs.
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