When to flatten
Use this before sharing filled forms, stamped PDFs or annotated files where appearances must remain visible.
Flatten PDF
Flatten annotations and form appearances into a stable PDF for sharing or archiving.
Free online toolNo install requiredTemporary filesMobile friendly
- Flatten annotations
- Stabilize form appearances
- Create shareable PDF
What changes
Flattening can make annotations harder to edit later, so keep your original file if you may need changes.
Output
A new flattened PDF is generated without changing your original upload.
How to use Flatten PDF
Complete the task in a simple upload → adjust → download workflow.
Upload your file
Drag and drop your file into the upload area or click to choose it from your device.
Choose options
Adjust page ranges, quality, format, margins or order if the selected tool offers controls.
Download output
Run the tool and download the generated result using the temporary secure download link.
Common uses
Practical document workflows where this tool is useful.
Process documents online
Work without installing desktop software
Download a temporary output file
Continue with related PDF tools
Privacy-first processingUploaded and generated files use temporary storage and are cleaned automatically.
Works in the browser where possibleCore tools such as merge, split, rotate, image conversion and text export use browser mode for normal files.
Review before sharingAlways check important outputs, especially converted, compressed or extracted documents.
Flatten PDF FAQ
Answers to common questions before processing files.
What does Flatten PDF do?
Flatten PDF helps you complete this PDF task online and download a processed file without installing software.
Are my files stored permanently?
No. PDFio uses temporary processing and temporary download links. Old uploaded and generated files are cleaned automatically according to the configured retention window.
Do I need to install software?
No. The public PDFio tools run in your browser or through the site processing engine, depending on the task.
Can I use this tool on mobile?
Yes. PDFio is designed for phones, tablets and desktop browsers. Large files work best on a stable connection.