What flattening does
PDF Flatten merges interactive elements — form fields, annotations and comments — into the static page content, producing a single-layer PDF.
- Locks fields and annotations
How do I flatten a PDF?
Flatten a PDF by uploading it and letting the tool merge all layers, form fields, annotations and comments into the static page content. The result is a single-layer PDF that looks identical everywhere and can no longer be edited field-by-field. It runs entirely in your browser.
- Merge form fields and annotations into the page
- Prevent further editing of fields
- Consistent appearance across all viewers
- 100% client-side
What is
PDF Flatten
The process of merging a PDF's interactive layers — form fields, annotations and comments — into the underlying page content so they become permanent, non-editable graphics.
PDF Tools
Related terms
form fillerPDF editor
Frequently Asked Questions
To lock in appearance.
Flattening makes filled form fields and annotations permanent so they display identically in every viewer and cannot be changed.
No, that is the point.
Once flattened, form fields become static content and are no longer separately editable.
Yes.
Flattening runs with pdf-lib in your browser; nothing is uploaded.
Detailed Explanation
How it works
The tool renders each interactive appearance into the page content stream and removes the interactive objects with pdf-lib.
- pdf-lib appearance flattening
Use cases
Finalise completed forms, lock signed or annotated documents, and ensure consistent display before printing or archiving.
- Finalise forms and signatures
Limitations
Flattening is irreversible; you cannot re-edit fields afterward, so keep an editable copy if needed.
- Irreversible
Privacy
Flattening is performed in your browser and the document is never uploaded.
- 100% local