PDF Editor

True PDF "editing" (like deleting or rewriting the original text of a document) is notoriously difficult because PDFs don't store fluid paragraphs of text.

A PDF stores absolute X/Y coordinates for almost every letter. If you change a word from "cat" to "elephant", the PDF engine has to recalculate the coordinates for the rest of the line and potentially re-flow the entire page, which is highly complex.

Instead of altering the underlying text stream, most PDF Editors (including this one) rely on Annotations (/Annots).

When you draw a circle or add a text box over a PDF, the original document's content stream is untouched. The editor simply appends an Annotation dictionary to the page object. This acts as a non-destructive, transparent overlay that sits on top of the original canvas.

Because annotations are overlays, if you draw a black rectangle over a Social Security Number to censor it, the underlying text is still embedded in the file. Anyone who opens the PDF in Acrobat can simply select and delete your black rectangle to reveal the text.

To make drawings permanent, you must Flatten the PDF. Flattening takes all interactive annotations and "bakes" them directly into the primary content stream. Note: For true cryptographic redaction (permanently scrubbing the underlying data bytes), use our Redact tool instead of this Editor.