Edit existing text inline
Click any text run and re-type it in place. Vellum reuses the document's own embedded font so the new glyphs match exactly.
On-device · MuPDF WASM · exact fidelity
The PDF editor that keeps your document byte-for-byte perfect
Edit, move, re-type and redact PDF content right in your browser. Anything you don't touch exports identical to the original — same fonts, positions and structure. No upload, no account.
MuPDF removes redactions
pdf-lib draws new content
re-render = export
A real object-level editor, not a converter
Most “PDF editors” flatten your file to HTML and back, wrecking fidelity. Vellum mutates the real PDF and re-renders from it.
True redaction
Deletions apply real MuPDF redactions — the content is removed from the file, not covered. It's gone for text extractors too.
Move text & graphics
Grab any region. Text stays live and re-editable; only genuinely graphical regions are captured as a high-res image.
Add anything
Drop in text boxes, rectangles, highlights, images and signatures — placed directly into the PDF stream, not an overlay.
Zoom to 1000%
MuPDF re-rasterizes at device-pixel scale, so the page stays crisp at any zoom via ⌘/Ctrl + scroll.
Private by default
Everything runs in your browser through WebAssembly. No account, no upload — your document never leaves your device.
The fidelity loop
1
Open
Pick a PDF (or generate a sample). It's parsed locally with MuPDF WASM.
2
Edit
Move, re-type, redact or add content. Each edit mutates the real PDF object model.
3
Bake
Redactions are truly applied and the page re-renders from the resulting PDF — view = export.
4
Export
Download a real .pdf, serialized from the same object model, editable in any reader.
Your documents never leave your device
Contracts, invoices and agreements are sensitive. Vellum runs the entire engine — parsing, editing, redaction and export — locally in your browser through WebAssembly. There is no server round-trip on the default path.
Frequently asked questions
Is my PDF uploaded to a server?
No. Vellum parses, edits and re-renders your PDF entirely in your browser using MuPDF compiled to WebAssembly. On the default path your file never leaves your device.
What does “exact fidelity” mean?
Any content you don't touch exports byte-identical to the original — same fonts, glyph positions, colors and structure. Every edit mutates the real PDF object model and the page is re-rasterized from that mutated PDF, so what you see is what exports.
Can I truly remove text, not just cover it?
Yes. Redaction applies real MuPDF redactions that remove the underlying content from the file — text and graphics both — so it is no longer extractable, not hidden behind a black box.
Does it keep the document's original fonts?
When a font's program is embedded in the PDF (TrueType or OpenType), Vellum extracts and re-embeds a subset of that exact font so edited text matches the original glyphs. Otherwise it falls back to the closest standard font.
How much does it cost?
The in-browser editor is free to use. Your files are processed locally, so there is no account and no upload required.