# PDF form field inspector

> Inspect field names, types and read-only status before form filling.

[Open tool](https://www.toolcabana.com/tk/pdf-form-field-inspector) · [PDF and documents](https://www.toolcabana.com/tk/category/pdf-and-documents)

Tool ID: pdf-form-field-inspector. Requested language: tk. Description language: en. Complete guide translation: no; untranslated sections use English.

## Overview (en)

PDF form field inspector lists the interactive fields in a PDF form in a table. Each row shows the field name, its type, such as text field, checkbox or dropdown, and whether the field is read-only. Use it to learn the exact field names before filling a form with JSON.

## Supported tasks (en)

Inspect field names, types and read-only status before form filling. Inspect schema rather than fill values.

## Steps (en)

1. Choose a source file. If the tool accepts multiple files, arrange them in the order you want.
2. Check the source format before running the operation.
3. Run pdf form field inspector, review the output, then use the available copy or download controls.

## Settings

No additional settings.

## Limitations (en)

Up to 200 files, 20 MB each and 100 MB combined. PDFs are limited to 500 pages, contact sheets to 100 pages, and bookmark trees to 1,000 entries and 20 nesting levels. Individual operations apply smaller output limits.

## Privacy and connections (en)

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

## Questions (en)

### How do I find the field names in a fillable PDF?

Load the PDF and run the inspector. The table shows every field's full name exactly as stored in the form, which you can copy as keys when filling the form with JSON values.

### What do the field types in the inspector mean?

Types are reported by their internal class names, such as PDFTextField for text boxes, PDFCheckBox for checkboxes and PDFDropdown for drop-down lists. They tell you what kind of value each field accepts.

### Why is my PDF showing no form fields?

The inspector reads interactive AcroForm fields. A form that only looks fillable, such as a scan or flattened document with drawn boxes, has no interactive fields, so the table comes back empty.

### Where is my input processed?

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

### What are the input limits?

Up to 200 files, 20 MB each and 100 MB combined. PDFs are limited to 500 pages, contact sheets to 100 pages, and bookmark trees to 1,000 entries and 20 nesting levels. Individual operations apply smaller output limits.

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