Actualizado en marzo de 2026

Fill PDF Forms Online Free

Auto-detect form fields in any PDF. Fill in text, checkboxes, and dropdowns, then download the completed form instantly.

Suelte el archivo PDF aquí

Upload a fillable PDF to auto-detect form fields

Tamaño máximo de archivo 10 MB. Regístrate para más.

Cómo completar un formulario PDF en línea

Fill out any PDF form in three simple steps. No software required.

Sube tu PDF

Drag and drop a fillable PDF onto the upload area, or click to browse your files.

Fill in Form Fields

Our tool auto-detects all form fields. Fill in text boxes, check checkboxes, and select dropdown options using the form on screen.

Download Completed PDF

Haga clic en descargar para obtener su PDF completo. Opcionalmente, aplana el formulario para bloquear tus respuestas de forma permanente.

Why Choose Our PDF Form Filler

Auto-Detect Fields

Automatically detects all interactive form fields in your PDF — text boxes, checkboxes, dropdowns, and more.

All Field Types

Supports text inputs, checkboxes, radio buttons, combo boxes, and list boxes for complete form filling.

Flatten Option

Opcionalmente, aplana el formulario para incorporar los valores al PDF de forma permanente, haciéndolo no editable para el envío final.

Lossless Quality

Only form field values are modified. All other PDF content — text, images, layout — stays exactly the same.

Form Data Never Stored

Your PDF and the data you enter are processed in-memory and deleted immediately after download. No form values are logged or retained on our servers.

No Adobe Reader Needed

Fill PDF forms in your browser without Adobe Reader, Acrobat, or any desktop software. Works on phones, tablets, and computers.

PDF Form Filler FAQ

Quick answers about filling PDF forms online, supported field types, and saving filled forms.

¿Cómo detecta el PDF Form Filler los campos automáticamente?

Our tool reads the interactive AcroForm fields embedded in your PDF's structure. It detects text inputs, checkboxes, radio buttons, and dropdown menus, then renders them as a simple web form you can fill out directly in your browser without any plugins.

What types of form fields are supported?

We support all standard PDF form field types: text fields, multi-line text areas, checkboxes, radio buttons, dropdown menus (combo boxes), and list boxes. Each field is rendered as its matching HTML equivalent so you can fill it out using familiar form controls.

What does the 'Flatten' option do?

El aplanamiento integra los valores completados permanentemente en el PDF como contenido estático y elimina todos los campos del formulario interactivo. Los valores ya no se pueden editar después de aplanarlos, por lo que es la opción recomendada al enviar formularios completos a organizaciones o para archivarlos.

What if my PDF doesn't have fillable fields?

If your PDF is a scanned image or was created without interactive form fields, our tool will notify you that no fields were detected. In that case, you can use our E-Sign PDF tool to add text, annotations, and signatures directly onto any PDF page.

¿Está seguro mi archivo PDF?

Yes. Your file is uploaded over an encrypted HTTPS connection, processed entirely on our server, and automatically deleted after processing completes. We never store, access, or share your documents or the data you enter into form fields.

Will filling the form affect my PDF quality?

No. Only the form field values are updated. All other content in the PDF — text, images, vector graphics, and page formatting — remains completely untouched. The output file retains the same visual quality as the original.

Can I fill out a PDF form created in Adobe Acrobat?

Yes. The tool supports standard AcroForm fields used by Adobe Acrobat, Foxit, and most other PDF editors. As long as the PDF contains properly embedded interactive fields, they will be detected and displayed for filling regardless of which software created the form.

Can I save a partially filled form and finish it later?

The tool processes forms in a single session, so you should complete all fields before downloading. If you download without flattening, the form fields remain editable and you can re-upload the PDF later to continue filling in any remaining fields.

Does the form filler support XFA forms?

Currently the tool supports standard AcroForm-based PDF forms, which cover the vast majority of fillable PDFs. XFA forms, which are an older XML-based format sometimes used in government and enterprise documents, are not supported at this time.

How do I know if my PDF has fillable form fields before uploading?

Most fillable PDFs show highlighted or outlined input areas when opened in a PDF reader. If you are unsure, simply upload the file — the tool will instantly tell you how many fields were detected or notify you if the PDF contains no interactive form fields.

PDF Form Filling Guides

Helpful articles about fillable PDFs, form submission workflows, and fixing common PDF upload or editing issues.

Cómo completar un formulario PDF en línea de forma gratuita: no se necesita Adobe

¿Necesita completar un formulario PDF pero no puede editarlo? Complete formularios PDF en línea de forma gratuita: funciona en formularios interactivos y archivos PDF escaneados planos. Sin Adobe, sin cuenta.

Herramientas relacionadas

Explora más herramientas gratuitas en iFormat.io

Firma electrónica de PDF

Agregue firmas electrónicas a cualquier documento PDF. Dibuja, escribe o sube tu firma.

Password Protect PDF

Encrypt the completed form so only intended recipients can open it.

Merge PDF Files

Combine multiple filled forms into a single document for submission.

Agregar números de página

Number pages of a multi-page form so reviewers can reference them clearly.

Comprimir PDF

Reduce the filled form’s file size for upload limits or email attachments.

Dividir PDF

Split a long form into separate sections or submission packets.