Flatten Adobe PDF Online
Flatten PDF annotations, comments, highlights, markups and form fields online while keeping how the pages look. See what’s inside your PDF first, choose exactly what to flatten, and check the result before you download. Works with PDFs made or edited in Adobe Acrobat and any other PDF app.
- 1 Upload
- 2 Choose Settings
- 3 Download
Step 1 of 3: Upload your PDF
Drop your PDF file here
or choose a file from your device
PDF only • Up to 50 MB
Drag & drop • Click to browse • No signup required
Your PDF is inspected in your browser. It is uploaded only when you flatten it, processed securely and removed automatically afterwards. Your original is never changed.
- 1 Upload your PDF
- 2 See what’s inside
- 3 Choose what to flatten
- 4 Flatten, check & download
Reading your PDF…
- Sent over an encrypted HTTPS connection
- Deleted automatically, normally within 60 minutes
- No registration needed · Privacy Policy
Flatten PDF
Check what was found, choose what to flatten, then flatten. Click a page number to jump to that page.
- 1 Upload
- 2 Choose Settings
- 3 Download
Step 2 of 3: Review what’s inside and choose what to flatten
What’s in your PDF
Inspecting your PDF…
This PDF may already be flattened, so there is nothing to flatten. Links and bookmarks are normal in a flattened PDF.
| Type | On pages | Count |
|---|
Select a page number to look at that page. Untick a type below to leave it editable.
Flattening or otherwise changing a signed PDF makes the signature stop validating. Signature fields themselves are not flattened. Keep a copy of the original before you continue.
- Tip: select a page number in “What’s in your PDF” to see the annotations on that page.
- Tip: to delete annotations instead of keeping them on the page, use Remove PDF Annotations.
Flattening your PDF…
0%
Uploading your file…
Original vs flattened · Page 1
The pages should look the same. What changes is that the markups are now part of the page instead of separate, editable comments.
PDF Preview
Here’s a look at your finished PDF.
Page 1 of 1
Result Summary
Save to Cloud (Optional)
Keep your file safe and accessible from anywhere.
Pick a folder in your own account, or share the file straight from here.
Useful Tips
- Check the summary: every check should say Passed. Anything marked Needs attention says what to look at.
- Want to stop copying or editing too? Flattening is not protection; add a password with Protect PDF.
- Not sure a file is flattened? Use Check if a PDF is flattened below the tool.
✨ Did you know? You can also compress, crop, merge and more — all in one place!
Explore All ToolsWhat would you like to do next?
See what is inside, choose what to flatten, check the result.
Getting started
- Upload your PDF.
- Review what was found, then choose what to flatten.
- Flatten, read the checks, compare with the original and download.
Key concepts
- Flatten
- An annotation or form field is drawn into the page and removed from the comment layer. It looks the same but can no longer be edited, moved or deleted as a comment.
- Remove
- Deletes annotations completely, so they disappear from the page. That is Remove PDF Annotations, not this tool.
- Form fields
- Filled-in values become plain page content. Empty fields leave their box, if it has one, and nothing else.
- Signatures
- Signature fields are never flattened, but any change to a signed PDF makes its signature stop validating.
- Not security
- Flattening does not stop copying or editing with a PDF editor. Use Protect PDF for a password.
- Your original
- It is never changed.
Tips & shortcuts
- Select a page number in What’s in your PDF to jump to that page.
- Password-protected PDFs need unlocking first with Unlock PDF.
- Enter confirms · Esc closes a dialog · ? opens this panel.
Did you know? Switching to another tool in the sidebar carries your file over automatically — no need to re-upload.
Still stuck? Read the questions below or contact support and we'll help.
Check If a PDF Is Flattened
Not sure whether a PDF still has editable comments or fillable fields? Check it here. The file is read in your browser and is not uploaded.
Drop a PDF here to check it
What Does It Mean to Flatten a PDF?
A PDF keeps comments, highlights, drawings, stamps and form fields in a separate layer on top of the page. Anyone with a PDF reader can select them, move them, change them or delete them. Flattening draws each of them into the page itself and removes it from that layer. The page looks the same, but the markup is now ordinary page content instead of an editable comment.
People flatten a PDF before sending a final version, so a reviewer’s highlights or a filled-in form arrive exactly as they were, and before printing, because some printers and viewers don’t print comments at all.
PDFCherry is not affiliated with Adobe. This tool works with PDFs created or edited in Adobe Acrobat and Acrobat Reader, as well as Preview, Foxit, Microsoft Edge and other PDF apps, because they all store annotations the same, standard way.
How to Flatten an Adobe PDF Online
Upload your PDF. It is inspected in your browser and you see what it contains.
Choose Everything, Annotations only or Form fields only, and untick any annotation types to leave editable.
Select Flatten PDF. The file is flattened and then checked automatically.
Read the checks, compare the original and flattened pages, and download.
How to Flatten Annotations in a PDF Online
To flatten annotations without touching fillable form fields, choose Annotations only. Each kind of annotation is listed with how many were found, so you can flatten all of them or leave some editable:
- Comments and sticky notes: the note icon stays on the page. The note text only ever appeared in a pop-up, so it is removed with the note. If the text must stay visible, type it onto the page as a text box first.
- Highlights, underlines and strikethroughs: keep their colour and transparency, so the text underneath stays readable.
- Freehand drawings, shapes and lines: become fixed in place.
- Stamps: Approved, Draft, Sign Here and image stamps become part of the page.
- Text boxes and typewriter text: stay as text you can still select and copy.
Flatten vs Remove vs Lock Annotations
| Action | Still visible on the page? | Can it be edited as a comment? |
|---|---|---|
| Flatten (this tool) | Yes | No. It is now page content |
| Remove annotations | No | No. It is gone |
| Lock (Acrobat’s “Locked” property) | Yes | Not until someone unlocks it, which anyone can do in its properties |
| Leave as is | Yes | Yes |
Flatten PDF vs Print to PDF
“Print to PDF” with comments turned on also makes markups permanent, but it rebuilds the whole file: links, bookmarks and form data are usually lost, text can come out in a different order or not selectable at all, and some printers leave comments out entirely. Flattening changes only the annotations and fields you choose and leaves the rest of the file as it was.
Flatten PDF vs Password Protection
They solve different problems. Flattening stops markups being edited as comments; it does not stop anyone copying text or editing page content in a PDF editor. A password from Protect PDF controls who can open the file and what they are allowed to do. For a final document you send out, you can do both: flatten first, then protect.
When Should You Flatten a PDF?
- Before sending a reviewed contract, drawing or report, so the markups arrive as they are
- Before submitting a completed form, so the values can’t be changed by accident
- Before printing, when comments or stamps don’t show up on paper
- Before merging or uploading to a system that drops annotations
- Not before signing: flatten first, then sign, because changing a signed PDF breaks its signature
Common PDF Flattening Problems
“My comments are still editable.”
Saving a PDF, or saving a copy, keeps annotations as annotations. They only become part of the page when the file is flattened, or printed to PDF with comments included. Check the file with Check if a PDF is flattened; if it lists annotations, flatten it here.
“I flattened the PDF but the form fields still work.”
Flattening annotations and flattening form fields are separate steps in many apps. Choose Everything or Form fields only here, and the form field check in the result confirms no fillable fields are left.
“My digital signature is no longer valid.”
A digital signature covers the exact bytes of the file when it was signed. Any change, including flattening, makes it stop validating. Signature fields are never flattened here, and you are warned before you start. Flatten the document first, then have it signed.
“The PDF looks different after flattening.”
The result is drawn from each annotation’s own appearance, so it normally looks identical, and every page is compared with the original after flattening. A difference usually means the annotation had no stored appearance and one was generated, or a form used fonts that are not embedded. Use the before/after comparison to look, and the checks to see which pages differ.
“I don’t know whether my PDF is already flattened.”
Use Check if a PDF is flattened. It lists any annotations and fillable form fields still in the file. Links and bookmarks are normal in a flattened PDF and don’t count.
“I don’t want to delete my comments.”
Flattening doesn’t delete them from the page; it fixes them in place. Deleting is a different tool, Remove PDF Annotations. Either way, keep your original file if you might want to edit the comments later, because flattening can’t be undone.
What This Tool Doesn’t Do
- One PDF at a time, up to 50 MB. There is no batch flattening yet.
- Hidden annotations, and annotations with no visible appearance, are left as they are and listed in the result.
- Redaction marks are not flattened: drawing them would cover content without removing it. Apply them with Redact PDF.
- Dynamic XFA forms (some government and tax forms) can’t be flattened safely; you’ll be told if your file is one.
- Want every page turned into an image so nothing can be selected? That is Rasterize PDF; text stops being searchable.
Flatten PDF FAQ
How do I flatten an Adobe PDF online?
Upload the PDF above, check what was found, choose Everything, then select Flatten PDF. When the checks have run, download the flattened file. It works the same for PDFs from Adobe Acrobat and any other PDF app.
How do I flatten PDF annotations online without flattening form fields?
Choose Annotations only. Comments, highlights, drawings, shapes and stamps become part of the page, and fillable form fields keep working.
Does flattening a PDF remove comments?
It removes them from the comment layer but keeps how they look on the page. Text that only showed in a sticky note’s pop-up is removed, because it was never part of the page.
Can I flatten PDF form fields?
Yes. Choose Everything or Form fields only. The values you typed become plain page content and the fields can no longer be filled in. Signature fields are not flattened.
Does flattening make a PDF uneditable?
It makes the flattened annotations and fields uneditable as comments and fields. It does not lock the document: text can still be copied and a PDF editor can still change page content. For that, add a password with Protect PDF.
Can I flatten a PDF without Adobe Acrobat?
Yes. This tool runs in your browser on any device, with no Acrobat or other software to install.
Can I flatten a PDF online for free?
Yes. It is free with no account, watermark or daily limit. Each file can be up to 50 MB.
Does flattening reduce PDF quality or remove links?
No. Pages are not turned into images, so text and images stay exactly as they were. Links stay clickable unless you untick Keep links clickable.
Does flattening invalidate a digital signature?
Yes. Any change to a signed PDF makes its signature stop validating. You are warned when a PDF has a signature field, so you can keep the original. Flatten before signing, not after.
Can I flatten a scanned PDF?
Yes, if someone has added comments, highlights or stamps to it. The scanned pages themselves are already images and are not changed.
How do I know if a PDF is already flattened?
Use Check if a PDF is flattened on this page. It lists any annotations and fillable fields still in the file, without uploading it.
Can I flatten multiple PDFs at once?
Not yet. Flatten them one after another; each result has a Flatten Another PDF button.
Can I undo flattening?
No. Once an annotation is part of the page it can’t be turned back into a comment. Your original file is never changed, so keep it if you may need the editable version.
Is it safe to flatten a PDF online?
Your PDF is inspected in your browser and uploaded only when you flatten it, over an encrypted connection. It is processed in its own folder and deleted automatically, normally within 60 minutes. No account is needed.
Privacy & Security
What happens to your file
The analysis, the page thumbnails, the before/after comparison and the flattened-PDF checker all run in your browser. Your PDF is uploaded only when you select Flatten PDF, over an encrypted HTTPS connection, and processed in its own job folder. The flattened file is deleted automatically, normally within 60 minutes, and your original is never changed. Read our Privacy Policy or contact us with any questions.
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