What is a PDF annotation, and why does whiting-out text not remove it?
An annotation is an object attached to a page on top of its content: highlights, underlines, strike-throughs, sticky notes, free text, ink drawings, shapes, stamps and signature fields are all annotation types defined in ISO 32000, stored in the page's /Annots array and editable or removable later. Flattening draws them permanently into the page content. The PDF editor on this site keeps only highlights, underlines, strike-throughs (unless you choose to flatten them) and sticky notes as annotations; the text, drawings, shapes, stamps and signature images it adds are written straight into the page content and are permanent. A white rectangle drawn over text is exactly that — a shape on top — so the text beneath still exists, copies and searches; only redaction, which deletes the underlying content, removes it.
Security note: Covering text with a shape is not redaction: the hidden text remains in the file and can be selected, extracted or found by search. Use a redaction tool that removes content, then check the result by searching for the removed text.
Read the guide: How to Edit a PDF Without Uploading It
How to use Strikethrough PDF
- Drop a PDF.
- Drag across the words to cross out.
- Pick a colour.
- Click "Save PDF" and download.
Strikethrough PDF features
- Line through the middle of every selected line
- Colour and opacity
- Standard StrikeOut annotation or flattened
- Highlight and underline on the same toolbar
- Local processing
Strikethrough PDF example
Mark a sentence for deletion
Input:
Drag over the sentence; redOutput:
draft-strikethrough.pdf — a StrikeOut annotation over two linesFrequently asked questions about Strikethrough PDF
Does striking through remove the text?
No — it marks it. The text stays in the file and remains searchable. To remove text for good, use Redact PDF.
Can I add a comment explaining the change?
Yes: add a sticky note next to it with Add Notes to PDF, or use the full editor where both tools are on the same toolbar.
Is my PDF uploaded to a server?
No. The file is opened and processed by your browser with WebAssembly and JavaScript; nothing is sent to Mutqan Soft or anyone else. Close the tab and the file is gone. Downloading the result needs a free account — no subscription, no payment.
Can I use it on a password-protected PDF?
Yes, if you know the password: the file list asks for it once and every operation then works on the decrypted pages. The output is saved without a password unless you protect it again.
Technical notes
Same quad construction as the highlighter; the appearance stream strokes the middle of each quad. The text itself is not modified — see Redact PDF for removal.
References
- ISO 32000-2:2020 — Document management — Portable document format — Part 2: PDF 2.0The current PDF standard: file structure, objects, pages, fonts, annotations, forms and encryption.
- PDF Reference — ISO 32000-1:2008 (PDF 1.7), Adobe copyThe freely readable PDF 1.7 specification: page trees, content streams, metadata, permissions and the standard security handler.
- PDF.jsThe open-source PDF renderer that draws PDF pages in the browser without a plugin — how documents are previewed locally.