What it does

Fill interactive AcroForm documents. A scanned page or a PDF without fields does not become a form.

When to use it

Use it for your own documents or documents you are authorized to edit. Keep the original and verify the output.

Steps

  1. Load the form and review field names, existing values and read-only fields.
  2. Enter text, check boxes and choose supported options; complete required fields.
  3. Save and inspect the preview. Open the downloaded copy in an independent reader.

Example

Empty Name field and unchecked Accept checkbox.

Name: José Muñoz and Accept checked, with other fields preserved.

Common mistakes

PDF 5 MiB/50 pages, up to 100 fields; output 20 MiB. No XFA, encryption or cryptographic signature fields.

Helvetica-compatible Latin text; unsupported characters are rejected. No PDF JavaScript execution or automatic flattening.

Limitations

PDF 5 MiB/50 pages, up to 100 fields; output 20 MiB. No XFA, encryption or cryptographic signature fields.

Helvetica-compatible Latin text; unsupported characters are rejected. No PDF JavaScript execution or automatic flattening.

Fill PDF forms

FAQ

Are documents uploaded?

Processing stays in your browser. Visiting the site downloads its resources, including OCR models when requested.

Should I check the result?

Yes. Keep the original and inspect the copy or recognized text before relying on it.

pdf-lib: PDF forms API