Are my files uploaded anywhere?

No. The PDF is parsed in your browser tab and saved with pdf-lib — all client-side. Nothing is uploaded, stored, or logged. You can verify in your browser's DevTools Network tab: there is no request firing when you save.

AcroForm is the standard PDF form format defined in the PDF specification — text fields, checkboxes, radio buttons, dropdowns, and signatures embedded as objects in the document. Most modern PDF forms (tax authority forms, application forms, contract templates) are AcroForms. This tool can read and write them. The other format, XFA, is Adobe-proprietary and not supported.

What does "Flatten on save" do?

Flattening converts the form fields into static page content — the values become part of the page graphics and the fields disappear. Use it when you want a final non-editable copy (for example to email a signed form). Leave it off if you want the recipient to edit the form further.

Can I add fields to a PDF that has none?

Not with this tool. Adding new fields requires a form designer — Acrobat or a tool like LibreOffice Draw. If you only need to type text on a page, use the PDF Annotator.

Are my values saved if I close the tab?

No. Field values live in memory until you click Download. Refresh or close the tab and they are gone. The downloaded PDF, of course, has the values baked in.

How do I sign a PDF form?

For a visible signature stamp, use the PDF Sign tool — draw a signature and place it on the page. For an AcroForm signature field, fill the form here and add the signature stamp via PDF Sign on the saved file. Cryptographic e-signatures (audit trail, certificate-based) are out of scope for any browser-based tool.

PDF Form Filler

Open a PDF form, fill the fields in your browser, and download a completed copy. AcroForm fields (text, checkbox, radio, dropdown) are detected automatically. Nothing is uploaded.

Drop a PDF form here or

Drop a PDF form onto the page or browse for one.
The tool detects the AcroForm fields and overlays editable inputs over each one. Use Previous / Next to move between pages.
Fill in the values. Tab moves between fields in their PDF tab order; checkboxes and radios respond to space.
Click "Download filled PDF" — values are written back into the form and you get a completed copy. Toggle "Flatten on save" off to keep the form editable.

What does it do?

A client-side AcroForm filler. The PDF is parsed with pdf-lib, every form field is enumerated, and the editor renders an HTML input over each field rectangle (text, textarea, checkbox, radio, dropdown). On save, your values are written into the form via the same library and the file is downloaded. With "Flatten on save" enabled, the values are baked into the page content so readers without form support — for example email previewers — still show the filled values. The PDF never leaves your device.

Example

Drop a tax form, government application, or any PDF with input fields. Each field becomes an editable input in the rendered view. Fill name / address / signature fields, tick the right checkboxes, and click Download. The result opens in any reader with the values shown in place.

Common errors and pitfalls

A handful of cases where AcroForm filling cannot help — most reflect how the PDF was authored, not a tool limitation.

Flat (non-AcroForm) PDFs. A PDF can look like a form but contain no programmatic fields. Common causes: a scanned document, a form designed for printing only, or a PDF exported from Word without enabling form fields. The tool reports "no fillable fields" — switch to the PDF Annotator to type text directly onto the page.
Password-protected PDFs. If a PDF asks for a password to open, the tool can't parse it. Run it through the PDF Restriction Remover first if you have permission, or open it in a reader to remove the password.
XFA forms. XFA is an Adobe-proprietary form format used in some legacy government and banking PDFs. Open-source PDF libraries (this tool included) cannot read XFA fields. Open the PDF in Adobe Acrobat, fill it there, or print + scan into a regular AcroForm.
Form fields drift after typing. If a field's overlay rectangle does not line up perfectly with the printed underlay, the PDF was authored with a mismatch between the visual page and the field metadata. Saving still produces correct values; only the on-screen overlay is offset. Toggle "Flatten on save" so the saved PDF anchors to the field metadata, not the underlay.
Field accepts the wrong format. Some fields enforce a format (date, currency, regex). The tool does not enforce formatting — type the value the form expects and it will save as-is. Most PDF readers will validate when the form is opened later.

Frequently asked questions

Are my files uploaded anywhere?: No. The PDF is parsed in your browser tab and saved with pdf-lib — all client-side. Nothing is uploaded, stored, or logged. You can verify in your browser's DevTools Network tab: there is no request firing when you save.
What is an AcroForm?: AcroForm is the standard PDF form format defined in the PDF specification — text fields, checkboxes, radio buttons, dropdowns, and signatures embedded as objects in the document. Most modern PDF forms (tax authority forms, application forms, contract templates) are AcroForms. This tool can read and write them. The other format, XFA, is Adobe-proprietary and not supported.
What does "Flatten on save" do?: Flattening converts the form fields into static page content — the values become part of the page graphics and the fields disappear. Use it when you want a final non-editable copy (for example to email a signed form). Leave it off if you want the recipient to edit the form further.
Can I add fields to a PDF that has none?: Not with this tool. Adding new fields requires a form designer — Acrobat or a tool like LibreOffice Draw. If you only need to type text on a page, use the PDF Annotator.
Are my values saved if I close the tab?: No. Field values live in memory until you click Download. Refresh or close the tab and they are gone. The downloaded PDF, of course, has the values baked in.
How do I sign a PDF form?: For a visible signature stamp, use the PDF Sign tool — draw a signature and place it on the page. For an AcroForm signature field, fill the form here and add the signature stamp via PDF Sign on the saved file. Cryptographic e-signatures (audit trail, certificate-based) are out of scope for any browser-based tool.