🔒 Flatten PDF

PDFs are structured in layers: the page content (text, images), interactive form fields, and annotations (comments, highlights, drawings). Flattening merges these layers together so interactive elements become part of the page itself — no longer editable, no longer removable by simple tools.

Flatten Forms uses PDF-native flattening — it merges the form field appearances into the page content stream. Text stays selectable and searchable, the file stays small, and the original rendering is preserved exactly.

Flatten Everything rasterizes each page into a high-resolution image. This is the nuclear option — text becomes pixels, so it's no longer searchable or copyable. Use it when you need maximum flattening or when the PDF has complex overlays that native flattening might not fully collapse.

No — the visual appearance is preserved exactly. All three flattening modes produce output that renders identically to the original. Only the interactive/editable layers are removed.

Yes — but only if the PDF opens without a password prompt (i.e. it has owner-permissions but no open password). If the PDF requires a password to open, please use the Unlock PDF tool first, then flatten the unlocked copy.

They become part of the page content — permanently visible. The highlighter markup, sticky notes, and drawings are baked into the pixels of the page. They can no longer be moved, edited, deleted, or hidden by disabling the annotation layer in a reader.

It depends on the mode. Flatten Forms typically produces a similar-sized or slightly smaller file. Flatten Comments increases size for pages with annotations (they become images). Flatten Everything always produces a larger file, often 3–10× larger, because every page becomes an image. For file size control, use the quality presets (150/200/300 DPI).

No. Everything happens in your browser using pdf-lib and pdf.js. Your file never leaves your device.