Why doesn't my PDF show any fillable fields?

Not every form-looking PDF has interactive fields — many are flat scans of paper forms, with nothing for software to detect. The tool will tell you when it finds none. For flat forms, the Edit PDF tool can place text at the right coordinates on the page instead.

Are the filled values permanent?

They're saved into the form, but the fields remain interactive — anyone with a PDF reader could still change them. When the values need to be final (a submitted application, an agreed figure), flatten the file afterwards with the Flatten PDF tool.

What about signature fields and other exotic field types?

Text, checkbox, dropdown, and radio fields are fully supported. Signature fields aren't fillable here — for a drawn signature, run the filled form through the Sign PDF tool.

Why do some fields have cryptic names like 'topmostSubform[0].f1_01'?

Field names are assigned by whoever built the form, and government forms in particular use machine-generated names. The fields are listed in the form's internal order, which usually follows the visual layout — cross-check against the original PDF if a name is ambiguous.

PDF Form Filler

Fill interactive PDF form fields directly in your browser.

Drop PDF files here or browse

Max 100MB per file

About Fill PDF Forms

Many official documents — tax forms, applications, insurance claims — are distributed as PDFs with interactive form fields. You can fill them in a desktop reader, but Convertora gives you a cleaner path: upload the form, and every field appears as a plain web input you can tab through and fill, with the result saved back into the PDF.

All four standard field types are supported: text fields, checkboxes, dropdown menus, and radio button groups. Values already present in the form — defaults, or entries from a previous session — load into the inputs, so you can revise a partially completed form rather than starting over.

Forms are usually the most personal documents people handle — names, addresses, ID numbers, income. This tool reads and writes the form entirely in your browser; nothing you type is transmitted anywhere.

How to use it

1Upload a PDF with interactive form fields (up to 100 MB).
2The tool scans the form and lists every detected field with its name — text boxes as inputs, checkboxes as checkboxes, dropdowns and radio groups as select menus.
3Fill in the values. Existing defaults are pre-loaded; change or keep them as needed.
4Click Fill & Download. The values are written into the PDF's form fields and the file downloads with a -filled suffix.
5If the values must be final, run the output through Flatten PDF — filled fields otherwise remain editable in any reader.

Common use cases

Completing government and tax forms without installing a desktop PDF suite.
Filling the same application repeatedly — re-upload, adjust the fields that changed, download.
Completing a form on a phone or tablet, where web inputs beat tapping tiny PDF widgets.
Entering data into vendor onboarding or insurance forms before flattening and returning them.

Frequently asked questions

Tips

Keep the original PDF open in another tab while filling, so you can see each field's label and context alongside its input.
The complete workflow for returnable paperwork: fill here, then Flatten PDF to lock the values, then Lock PDF if it needs a password in transit.

100% private — runs in your browser

Convertora processes everything on your device using JavaScript and WebAssembly. Files never leave your browser, are never uploaded to a server, and are never seen by us or anyone else. The moment you close the tab, the data is gone — there is no temporary cloud copy, no log entry, no retained backup.

Because the work happens locally, processing speed depends on your device — but there are no rate limits, no daily caps, and no file size restrictions beyond what your browser can handle in memory. No signup, no account, no payment. The tool works the same in incognito mode, on a corporate network, or after the page has loaded once, even with the network disconnected.