pdfMB

Fill PDF form

Type into the fields of a PDF form and save it. Thai text stays correct in every PDF app, and your file stays on this device.

  • No uploadYour file stays on this device.
  • Your original stays as it isYou download a new copy. Your file is never changed.
  • Free, no sign-upNo account and no daily limit.

What happens to your file

Everything below happens inside your browser, on your own device. The PDF is not uploaded, so nobody else, including us, can see it or what you type.

  1. Your browser reads the form’s fields: text boxes, checkboxes, round choice buttons, drop-down lists and list boxes, with their position on each page.
  2. Each page that has fields is drawn as a picture with pdf.js, and a box is shown over every field. What you type appears in its box straight away, so you can see where it will go.
  3. Most forms don’t give their fields readable names. pdfMB uses the field’s description if it has one, and otherwise the words printed next to or above the field.
  4. When you save, each answer is stored in its field, and pdfMB draws how the field looks with a font that has every letter you typed: Helvetica for English, Sarabun for Thai, Vietnamese and other Latin letters. Only the letters you used are embedded.
  5. Thai lines are broken between words, not in the middle of a word, and “ำ” is marked so that copying the text gives the right character.
  6. The PDF no longer asks apps to redraw the fields themselves, because many apps redraw them with a font that has no Thai letters.
  7. An Adobe XFA copy of the fields, if there is one, is removed, so Adobe Reader shows the same answers as every other app.
  8. If you choose to lock the answers, each field is drawn into the page and then removed from the form.
  9. The new PDF is saved straight to your downloads. Your original file is not changed.
In short
  1. Choose a PDF form
  2. Type your answers
  3. Press “Save filled PDF”
  4. Download the PDF

How to fill in a PDF form

  1. Choose a PDF form or drop it on the box. pdfMB finds every field and shows how many there are.
  2. Type your answers in the list under each page. Tick checkboxes, pick choices and select items from lists. Tap a box on the page picture to jump to its field.
  3. Turn on “Lock the answers (flatten)” only if no one should change them later.
  4. Press “Save filled PDF” and download the new file. A picture of the saved page shows how it will look.

Why Thai answers often break in other PDF form tools

A form field stores two things: the text you typed, and a drawing of how the field looks. Many tools only store the text and leave the drawing to the PDF app, which uses the form’s own font. Most forms use Helvetica, which has no Thai letters, so Thai shows up as empty boxes, question marks or nothing at all.

Other tools draw the field themselves, but with a font without Thai letters. In our test, a widely used open-source PDF library did this silently and wrote “?????” in place of a Thai name.

pdfMB draws every field itself with a Thai font embedded in the file, puts tone marks and vowels above and below in the right place, and we check the result with three different PDF engines.

When people use it

Application and registration forms

Fill in a job, school, visa or membership form that came as a PDF, without printing it and writing by hand.

Thai government and company forms

Type your name and address in Thai into a fillable form and send it on. Tone marks and vowels stay in place in every PDF app.

Tax and bank forms

Complete forms such as a W-9 on any device. Your details stay on your device while you type them.

Forms you fill again and again

Keep the fields editable, then open the saved file next time and change only what is new.

What it can’t do

  • It fills forms that have real fields. Scanned forms and forms made only for printing have no fields; use Sign PDF to put text on them.
  • Forms that exist only in Adobe’s XFA format can’t be filled. Only Adobe Acrobat and Reader can fill them.
  • Calculations, date formats and checks that some forms run with JavaScript are not run.
  • Signature fields are not signed. Save the form first, then add a signature picture with Sign PDF.
  • Thai, Vietnamese and Latin letters are written as real text. Letters that need another font, such as Chinese, Japanese or Arabic, are drawn as a picture inside the field, while the field still holds the real text.
  • PDFs with a password, and PDFs whose owner blocked changes, can’t be filled.

Questions about filling PDF forms

Is my PDF uploaded?

No. pdfMB fills the form inside your browser, and neither the file nor your answers leave your device. You can check this in your browser’s network tools.

Will the answers show in other PDF apps?

Yes. pdfMB draws each filled field itself and saves that drawing in the file, so apps don’t need to redraw it. We checked the result in three different PDF engines.

Can I type in Thai?

Yes. Thai is written with an embedded Thai font, tone marks and vowels sit in the right place, and long lines break between words.

Can I change my answers later?

Yes, unless you choose to lock them. The fields stay editable in other PDF apps, and you can open the saved file here again.

What does “Lock the answers (flatten)” do?

It draws your answers into the page and removes the fields, so the answers can no longer be changed. Use it for a final copy.

Why does my PDF say it has no fields?

It may be a scan or a form made for printing. Such forms only look like forms. You can add text, the date and a signature with Sign PDF.