Fill PDF Form Online — Type, Save, Flatten

Fill AcroForm fields of a PDF and save it editable or flattened, in the browser

Runs in your browser · nothing is uploaded

Drop the PDF form to fill here

Add one PDF (up to 100 MB). Adding another file replaces the current one. Files never leave your browser.

What it does

This tool fills PDF forms such as applications, school forms and company templates without printing them. Upload the PDF and every field is listed, grouped by page; type text, tick boxes and choose options, then save a new PDF. When a field name is technical, like topmostSubform[0].Page1[0].Name[0], the form’s tooltip text or the last part of the name is shown instead.

How to use

Drop one PDF form on the box or press Choose PDF.
Fill the fields listed by page: type in text fields, click check boxes and choose radio, dropdown and list options.
Turn on Flatten after filling if nobody should change the values.
Press Save PDF and download the result. A preview of a page with a changed field appears below.
Restore the original values starts over.

How it works

Reading fields: pdf-lib reads the AcroForm fields with their kind (text, check box, radio, dropdown, list, signature, button), current value, options and the read-only, required, multi-line and maximum-length flags. Signature and button fields are shown with a note only.
Appearances: changed fields and fields without an appearance are drawn again. When the form sets NeedAppearances (asking viewers to redraw), stored appearances may be stale or empty, so every text and choice field is redrawn too, untouched ones included (Hangul with Noto Sans KR). NeedAppearances is then switched off so every viewer shows the same thing. In forms without that flag, untouched fields keep their original look.
Character limits are counted like PDF viewers count them (UTF-16 units): a Hangul syllable counts as one, an emoji as two.
XFA: for forms that also contain XFA data, the XFA part is removed on save and the values go into the regular fields. XFA-only dynamic forms have no fields to list.
Flattening works like the Flatten PDF tool (ISO 32000-1 section 12.5.5): field appearances are drawn into the page and the form is removed.
Libraries: pdf-lib (MIT), @pdf-lib/fontkit (MIT), Noto Sans KR (SIL OFL 1.1) and PDF.js (Apache-2.0) for the preview.

Examples

Goal	Settings
Fill and email an application	Fill → flatten after filling → save
A form a colleague continues	Fill → save without flattening
Only tick some boxes	Click the boxes → save
Add a signature too	Save the form, then place a signature with Sign PDF

To sign a filled form, use Sign PDF; to lock a form that is already filled, use Flatten PDF.

FAQ

Which PDF forms can I fill?

PDFs with interactive fields (AcroForm). Text fields, multi-line fields, check boxes, radio buttons, dropdowns and list boxes are found and listed. Scanned paper forms without fields are reported as having no fields; for those, place text or a picture with the PDF watermark or sign tools.

Will Korean or other non-Latin values show in other viewers?

Yes. The appearance of every changed field is drawn when saving, and text with non-Latin letters embeds the Noto Sans KR font for it. Viewers that do not pick a fallback font, such as browser and phone viewers, then show the values correctly. Chinese characters and emoji are not in that font; they are left out and listed in the result.

Can the recipient change the values?

By default the form stays interactive, so yes. Turn on “Flatten after filling” to make the values part of the page and remove the form.

Why does a total field not calculate?

Form scripts (JavaScript calculations and validation) are not run, for safety. Fill calculated fields such as totals yourself.

What about fields with a character limit?

The limit is shown next to the field name, and an overlong value is reported before saving. Read-only fields are locked. Empty required fields are listed as a reminder but do not block saving.