PDF Form Creator & Filler

What is an AcroForm?

A PDF form is a PDF that has interactive fields a reader can fill in: a text field, a checkbox, a radio-button group, a dropdown. The PDF specification defines those fields and their behaviour in the AcroForm dictionary — a top-level structure that lists each field, its type, its position, its default value, and its current value.

When you open a tax form, a vendor onboarding form, or a school enrolment form in any modern PDF reader, you’re looking at an AcroForm. The reader exposes each field for typing, your input is stored in the form’s value dictionary, and saving produces a PDF whose AcroForm now carries the filled values.

There’s a second technology — XFA, Adobe’s XML Forms Architecture — that was sometimes used for very dynamic forms (reflowing layouts, scripted logic). XFA was deprecated in PDF 2.0 because it never escaped Adobe’s own ecosystem. Today, AcroForm is the practical universal standard and this tool focuses there.

What this tool does

PDF Forms has two modes:

• Create. Start with a blank A4 PDF, add text fields and checkboxes by clicking on the page, label them, set default values, and export. The result is a normal AcroForm-bearing PDF that any reader can fill.
• Fill. Load an existing AcroForm PDF, see every form field listed, edit each value inline, and save. The result is the same PDF with the field values populated.

Both modes use pdf-lib to read and write the AcroForm dictionary directly. No upload, no server-side form engine.

Create mode: building a form

The Create flow is:

1. The tool starts with a blank A4 page (595 × 842 PDF points).
2. Click on the page to place a text field at that position. You can resize the field, set its name, and optionally set a default value.
3. Toggle to Checkbox to place checkboxes the same way.
4. The field list on the side shows every field you’ve added with its name and position; click any entry to edit or delete.
5. Export. pdf-lib writes the AcroForm dictionary with one entry per field, sets each widget annotation, and saves a standard PDF.

This is intentionally a simple-form builder. For complex multi-page forms with conditional logic, professional form designers (Adobe Acrobat Pro, LibreOffice Draw’s form mode, specialised tools) cover ground this doesn’t.

Fill mode: filling an existing form

The Fill flow is:

1. Drop an AcroForm PDF onto the dropzone.
2. The tool calls getForm() on the loaded document and enumerates every field: name, type, current value.
3. For text fields, you get an input box; for checkboxes, a tick-box; for radio groups, the option list; for dropdowns, the choices.
4. Edit the values inline.
5. Click Save. pdf-lib writes each new value into the matching field and saves a new PDF. The original is untouched.

Signature fields and button fields are listed but not editable here — see Sign PDF for the signature flow.

Common use cases

• Internal reusable forms. Timesheets, leave requests, equipment checkout sheets, expense report headers. Build once in Create mode, hand the empty PDF to colleagues, fill in Fill mode (or any other reader) on each use.
• Filling vendor onboarding forms. A counterparty sent you a 12-page W-9 / vendor questionnaire / NDA cover sheet as an AcroForm. Fill mode lists every field, you type each one, download, send back — no printing-signing-scanning.
• Government and school forms. Tax forms, school enrolment forms, registration paperwork that came as AcroForm PDFs. Fill mode handles them natively.
• Replacing handwritten internal paperwork. A team that still circulates a printed form for sign-off can move to a fillable PDF in an afternoon — Create the form here, share the empty PDF, fill on each use.
• Quick mock-ups of paper forms. Designing a new internal process; build a working fillable PDF here before committing to a full form-engine integration.

How to use this PDF Forms tool

Create mode:

1. Open the tool and stay on the Create tab.
2. Click on the blank A4 preview where you want a text field. Drag to set its size.
3. Name the field (the name is what shows up in the AcroForm dictionary — keep names unique and predictable).
4. Repeat for every text field. Toggle to Checkbox for checkbox fields and click to place them.
5. Click Export PDF to download the empty fillable form.

Fill mode:

1. Switch to the Fill tab and drop an AcroForm PDF.
2. The field list appears on the right; the page preview on the left highlights each field as you focus its row.
3. Type into each text field; tick checkboxes; pick from dropdowns.
4. Click Save PDF to download the filled version.

Security and limits considerations

• AcroForm only. XFA forms (rare, mostly legacy Adobe forms) aren’t supported. If the field list comes up empty on a file that “looks like a form”, suspect XFA.
• Signature and button fields are not editable. They’re shown for completeness but require their own workflows.
• Encrypted PDFs need to be unlocked first. Use PDF Password Remover before opening in Fill mode.
• Field validation isn’t enforced. PDF supports field-level format validation (date masks, numeric ranges) via JavaScript actions embedded in the form. Those run in Acrobat / Reader, not here — type the value you intend and trust the receiving end to validate.

Privacy

Form creation and form filling both run entirely in this browser tab. The empty form (Create) or the filled values (Fill) live in memory and in the PDF you download. There is no server, no submission, no cloud storage. The only network requests this page makes are for its initial JavaScript bundle.

Compatibility notes

The output is a standard AcroForm-bearing PDF, readable and fillable in every modern PDF reader: Adobe Acrobat, Apple Preview, the browser viewers in Chrome / Edge / Firefox / Safari, mobile PDF readers, and any other tool that supports the PDF spec. Filled values display the same way everywhere; text-field appearance is generated by the reader from the field value and the font in the appearance stream.