Flatten PDF Annotations and Markups
Flatten PDF comments and markups so they are drawn permanently onto the page and can no longer be edited. Form fields stay fillable unless you choose to include them.
Tool workspace
Nothing is uploaded. Files are read in this tab and stay on your machine.
Flatten annotations onto the page
Save your download before you leave the page — it exists only in this tab.
How do I flatten PDF annotations and markups?
Select one PDF. Every annotation is listed with whether it can be flattened and why not where it cannot.
Choose the pages, and decide whether to include interactive form fields and hidden annotations.
Select Flatten annotations and save the result before leaving the page.
What does flattening a PDF do?
Flatten a PDF’s annotations and markups: each comment, highlight or cloud is drawn permanently into the page, so it prints and displays the same everywhere, and the annotation itself is removed. Interactive form fields are held separately and are left alone unless you include them.
Most annotations carry an appearance stream: a stored drawing of how they look. Flattening fits that drawing to the annotation’s box on the page and writes it into the page content. The stored drawing may itself be turned or scaled, so that is applied first and only then is the result fitted to the box; doing it the other way round moves every rotated or scaled markup, and the error is invisible on the common case. An annotation with no stored drawing is not flattened at all, because its look is whatever the reader decides and inventing one would produce a document that no longer matches what you saw. If your review runs in Xenmark, its comment plan PDF already shows every numbered comment in place on the drawing; this tool does the equivalent for markups made in other PDF editors.
How Xenmark makes it easy to flatten PDF annotations and markups
Markups become part of the page
Each comment, highlight or cloud with a stored appearance is drawn into the page content, and the annotation itself is removed.
Nothing leaves your machine
Nothing is uploaded. Files are read in this tab and processed in memory, with no account and no server for them to go to.
An outcome for each annotation
Annotations are listed by page and type with what happened to each, and where one cannot be flattened the reason is given.
Rotated and scaled markups land in place
Each stored drawing is turned and scaled the way the file says before it is fitted to its markup’s box, so rotated or resized markups stay where they were drawn.
Hidden markups stay hidden by default
Annotations someone marked as hidden are not drawn into view unless you tick the option to include them, and markups on a layer stay on that layer.
Nothing to install
It runs in the browser you already have. There is no plug-in, no desktop application and no sign-up to get through first.
Limitations
What this tool does not do, stated up front.
Flattening cannot be undone. The annotations are gone from the result, their text can no longer be extracted as comments, and a tagged (accessible) PDF loses its tags; the result says when that happens.
Interactive form fields are excluded by default. Flattening one destroys the control and the value in it, and no tool can read that value back afterwards.
An annotation with no stored appearance is left interactive and reported, never redrawn from a guess.
Questions
Why were some annotations left alone?
Each was left for one of three reasons: it has no stored drawing of how it looks, so its look depends on the reader; it is a link, which is kept working; or it is a form field or hidden annotation that you did not include. The table says which applied to each one.
Can I unflatten a PDF?
Not from the result. Keep the original: the flattened copy no longer holds the annotations as annotations.
What happens to form fields?
Nothing, unless you include them: they stay fillable in the flattened copy. Flattening a field draws its current appearance and destroys the control and the value, which is a different act from making a comment permanent.
Why did Xenmark build a free annotation-flattening tool?
Xenmark AS is a Norwegian software company building browser-based drawing review tools for owners, consultants, operators and other teams that receive and review technical drawings. Those teams handle PDFs every day, and not every file should be sent to a website just to merge, split or check it — a tender document, a client’s drawing set, a revision that is not released yet. So these everyday tools are free and run entirely in your browser: no account, no upload step, and no server ever receives the file. You can check that yourself — open your browser’s network tab, flatten a marked-up sheet, and watch nothing leave. What this tool cannot do is listed under Limitations above.
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