How to Fill a PDF Online Free

Filling a PDF used to mean buying Adobe Acrobat or printing the document, writing on it by hand, then scanning it back in. That whole workflow is obsolete. In 2026, you can fill a PDF online free in your browser in under three minutes - no software, no signup, no watermark.

This guide shows you exactly how to do it, on any device. By the end you'll know how to fill out any PDF — a job application, a rental form, a school enrollment sheet, a tax document — directly in your browser.

Why fill a PDF online instead of using desktop software

Desktop PDF editors like Adobe Acrobat cost money, take up disk space, and need regular updates. Browser-based tools need none of that. You open a URL and you're already using it. The advantages are real:

• Zero installation — nothing to download, nothing to update
• Works everywhere — Windows, Mac, Linux, Chromebook, Android, iPhone, iPad
• Privacy-first — the PDF stays on your device, never uploaded
• Fast — the tool is ready the moment the page loads
• Free forever — no subscriptions, no trials, no credit card

If you've ever searched for "fill a PDF online free" and ended up on a site that required an account or slapped a watermark on your document, you know how frustrating it is. FillPDF.app was built to solve exactly that problem.

What you need

Almost nothing:

• A PDF file you want to fill
• A modern web browser — Chrome, Safari, Firefox or Edge
• Two minutes

That's it. No account, no email, no credit card, no installation.

How to fill a PDF online free — step by step

Step 1: Open FillPDF.app

Go to FillPDF.app. You'll see a large upload box with a Choose PDF button and a note that your file is processed in your browser.

Step 2: Upload your PDF

Pick whichever method you prefer:

• Click Choose PDF and select the file from your device
• Drag the PDF file directly onto the upload box

The file is read directly into your browser's memory. It is not sent anywhere — no server, no cloud, no third party.

Step 3: Wait for the PDF to render

Within a second or two, your PDF appears on screen. If it has multiple pages, you'll see a page navigation bar at the bottom.

If your PDF contains fillable form fields (the kind you can normally click into), FillPDF.app detects them automatically and turns them into live inputs you can type in directly.

Step 4: Pick your tool

The toolbar has everything you need:

• Text — type anywhere on the page
• Number — opens a digits-only keyboard, perfect for phone numbers and ZIP codes
• Email — a keyboard with @ and . always visible
• Check — add a checkmark or an X
• Date — insert today's date with one click
• Sign — draw your signature with a mouse, stylus or finger
• Highlight, Draw, Box, Arrow, Whiteout, Image — everything else you might need

Step 5: Add your content

Click anywhere on the page where you want to add content. For text, an editor opens and the built-in on-screen keyboard appears. Type your information, then press Done.

You can add as many pieces of text, checkmarks, dates and signatures as you need. There's no limit and no cost.

Step 6: Reposition anything that needs adjusting

Tap Select, then tap once on any item you've added. A blue dashed outline appears along with a directional pad in the options bar. Use the arrow buttons (◀ ▲ ▼ ▶) to move it precisely, or drag it with your finger.

Step 7: Download your completed PDF

Click Download Filled PDF. The completed document is generated in your browser and saved to your device. Your original file is untouched — the download is a new file with -filled.pdf appended to the name.

Does it work with fillable PDFs?

Yes. If your PDF has interactive form fields (AcroForm fields), FillPDF.app detects them the moment the file loads. You'll see the fields highlighted on the page, and you can click into any of them and type directly — just like you would in Adobe Reader.

What about PDFs that aren't fillable?

Also yes. Scanned PDFs, image-only PDFs and PDFs exported from other software often have no interactive fields at all — they're just pages of static content. FillPDF.app handles those too: use the Text tool to place text directly on top of the page, position it wherever it belongs, and download. The result looks exactly the same as filling out a paper form.

For a deeper look at the difference, see How to Fill Out a PDF Online Free.

Does it work on iPhone and Android?

Yes — and it works better than most mobile PDF tools. FillPDF.app includes its own built-in keyboard that appears at the bottom of the screen when you tap to add text. That means you never have to fight with the native iOS or Android keyboard that sometimes refuses to open inside a browser tab.

The toolbar scrolls horizontally, all buttons are finger-sized, and the signature pad accepts touch input directly.

Is it really private?

Yes. Your PDF is processed entirely in your browser using JavaScript. It is never uploaded to a server, and no copy is stored anywhere. When you close the browser tab, the file is discarded from memory.

This is different from cloud-based PDF editors, where your document is uploaded to their servers, processed remotely and (theoretically) deleted afterward. With FillPDF.app, there's no upload step at all.

Common questions

Do I need an account?

No. There's no signup, no login, no email verification. Open the site and start filling.

Is it really free?

Yes. There's no trial, no watermark, no upgrade prompt, no credit card.

Can I add my signature?

Yes. Pick the Sign tool, draw your signature on the pad with your mouse or finger, then tap the page to place it. You can resize and reposition it before downloading.

Can I fill a PDF that someone scanned?

Yes. Use the Text tool to type over the scan. Position the text box over the blank area of the form and type your content.

What file size can it handle?

PDFs up to 50 MB are supported. Most forms are under 5 MB, so this covers essentially every real-world case.

Will it work without an internet connection?

No — the page itself needs to load first. But once loaded, all the PDF processing happens locally on your device.

Try it yourself

Reading about it is fine, but the fastest way to understand it is to just try it. Open FillPDF.app, drop in any PDF, and you'll have a filled document in under three minutes — guaranteed.