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Flatten PDF

Lock a filled-in form so nobody can change the answers. Flattening turns form fields into ordinary page content, which also fixes forms that print blank.

Select a PDF to flatten

Drag & drop here, or choose from your device.

PDF files · up to 100.0 MB each

Privacy note: this tool runs entirely in your browser using JavaScript. Your file is read into memory on your own device and is never uploaded to PDFQuick or any third party. Read our privacy policy.

When to use Flatten PDF

  • Lock filled-in form answers so they can't be changed after sending.
  • Make annotations print reliably on every printer.

Tips for better results

  • Use lock mode to rasterise pages when you need to make hidden content unrecoverable.

Good to know

  • Flattened form fields can no longer be edited.

How to use Flatten PDF

  1. Add your filled form

    Choose the completed PDF, up to 100 MB.

  2. Choose how far to go

    Flatten the fields only, or flatten the whole page to images for maximum lock-down.

  3. Download

    Save the flattened copy and send it on with confidence.

Why use PDFQuick for this

Answers can't be edited

Filled values become part of the page instead of editable fields.

Prints correctly

Fixes the common problem of form answers disappearing when printed.

Opens anywhere

Flattened pages look identical in every reader, phone or browser.

Stays on your device

Your completed form is never uploaded to a server.

Frequently asked questions

Can flattening be undone?

No. Keep the editable original if you may need to change answers later.

What if my PDF has no form fields?

It is simply rewritten and cleaned. Tick the images option if you want the appearance fully locked.

Are signatures kept?

Visible signature images and drawn marks stay. Cryptographic digital signatures are invalidated by any edit.

Does it stop people editing text?

Field answers become fixed. For a complete lock, use the flatten-to-images option.

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