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Flatten PDF

Lock form entries and annotations into the page. Turn filled form fields, comments, highlights and stamps into ordinary page content, so they look the same everywhere and can no longer be edited.

Never uploaded See what will be flattened No signup

Choose the PDF to flatten

We count its form fields and annotations in your browser.

Single file · Max 256 MB

Core processing stays in this browser after the page loads. Large files use device memory and may run slower.

Flatten PDF / lock it in

Make filled forms and comments look the same in every viewer, and stop them being changed.

Quick answer

How do I flatten a PDF?

Add your PDF, choose whether to flatten form fields, annotations or both, then download the flattened copy. Filled-in values, highlights, comments and stamps become part of the page, so they display the same in every viewer and cannot be edited. Links stay clickable. It runs in your browser, so the file is not uploaded.

Privacy by default

Flattening runs locally in this browser tab. Your PDF stays on your device while a flattened copy is created.

The flatten workflow

How to flatten a PDF

Choose what to flatten, download

  1. 01

    Add your PDF

    Choose the file; its form fields and annotations are counted.

  2. 02

    Choose what to flatten

    Select form fields, annotations or both.

  3. 03

    Download the flattened copy

    Save the new file; your original stays unchanged.

Why flatten a PDF

Lock in what is on the page

Forms, comments and stamps

01

Forms and annotations

Flatten filled-in form fields, comments, highlights, stamps and drawings, together or separately.

02

Looks the same everywhere

Flattened content no longer depends on a viewer’s form or comment support.

03

Links keep working

Hyperlinks are left clickable; only visual annotations are flattened.

04

See before you flatten

The tool counts form fields and annotations first, so you know what will change.

05

Works locally after the page loads

The PDF is flattened in your browser tab and never sent to a server.

06

No account required

Open the tool and use it without registration or a subscription.

Forms, annotations and editing

Flatten PDF FAQs

Forms, annotations and editing

What does flattening a PDF do?

It turns interactive parts, such as form fields and comments, into ordinary page content. The result looks the same, but the fields and annotations can no longer be edited, moved or deleted.

When should I flatten a PDF?

Before sending a completed form, so the answers cannot be changed and display the same in every viewer, or before printing or archiving a reviewed document with comments and stamps.

Can I undo flattening?

Not in the flattened file. Your original stays unchanged, so keep it if you may need to edit the form or comments again.

Will links still work?

Yes. Hyperlinks are kept as clickable links; only visual annotations are flattened.

Why was an annotation not flattened?

Some annotations have no stored appearance, so there is nothing to draw. They are left as they were, and the tool tells you how many.

Is my PDF uploaded?

No. The file is flattened in your browser tab and never leaves your device.

Learn before you process

PDF guides for this workflow

Get the answer, understand the trade-offs, then use the focused tool when you are ready.

How to sign a PDF online (and what a visual signature is)

Add a typed, drawn or image signature to a PDF, place it, and know when you need a certificate-based digital signature instead.

Read the signing guide

Best private PDF tools: browser-local vs cloud

A neutral guide to choosing a PDF tool when privacy matters: the questions to ask, a five-minute test you can run yourself, and which kind of tool fits which document.

Read the privacy guide

Comparing PDF tools? FreePDFKit vs iLovePDF · FreePDFKit vs Smallpdf · Browser-local PDF processing vs cloud upload

Related PDF tools

Verify it yourself

Your file is not uploaded. Here is how to check.

The core tools run inside your browser tab, so a document you open here is not sent to FreePDFKit or to anyone else. You can confirm that in about a minute.

  1. Step 1

    Open the tool and let it load

    Wait until the page has finished loading.

  2. Step 2

    Open your browser’s developer tools

    Press F12 (or Cmd+Option+I on a Mac) and switch to the Network tab.

  3. Step 3

    Run the tool on a test file

    Choose a non-sensitive file of the type the tool accepts and process it as usual.

  4. Step 4

    Look for a request that carries the file

    You will not find one. The page loads its own scripts, then the work happens in your browser.

What backs this up

  • Open-source libraries in the page. PDF handling uses libraries such as pdf-lib and Mozilla’s PDF.js, which run in your browser.
  • No PDF endpoint on the server. The only server routes are the contact form and the social-preview image generator.
  • A restrictive security policy. The site’s Content-Security-Policy limits the fetch and XHR connections page scripts can make to our own origin and Cloudflare’s anti-spam check, plus Google Analytics, which receives page views only.

Step-by-step checks, including an offline test, in how to check if a PDF tool uploads your file. More detail in the privacy policy and how this compares with other no-upload options.