# Unlock PDF: Remove the Password from Your PDF

> A free online tool that removes the password and the permission limits from a PDF when you type its password (the one that opens the file, or the owner password); it does not guess, crack or recover passwords.

Unlock PDF is a free online pdf unlocker that removes the password and permission limits from a PDF when you enter the password for that file. It does not crack, guess or recover passwords. If you do not know the password, the tool cannot open the file, and we cannot help. Use it only for files you own or have the right to open, as set out in our Acceptable Use Policy.

## Key facts

- Input: one password-protected PDF up to 10 MB without an account (50 MB signed in), up to 100 pages (500 signed in), and its password (1 to 127 bytes).
- The tool tries only the one password you type, with no retries and no variations, and does not guess, search for or recover passwords; without the password it cannot open the file. A PDF that opens without a password but limits printing, copying or editing needs its owner password.
- It supports user passwords, owner passwords, RC4 40-bit and 128-bit, AES-128 and AES-256; encryption with a certificate is not supported. The result is unlocked.pdf with no password and no limits, and a digital signature can become invalid because the file changes.
- The password is sent over HTTPS, kept only in encrypted form while the job waits, never written to the database or the logs, and deleted when the job ends; after 10 wrong passwords for the same file within 24 hours, further attempts on that file are refused, even with the right password.
- In our test a generated 6 page PDF of 51 KB protected with AES-256 became 53 KB, and unlocking it with its password gave a 52 KB PDF with 6 pages that reports Encrypted: no and has the same 1409 characters of text; results vary with the file.
- API: POST the PDF to https://api.aiipworld.com/v1/uploads, then POST https://api.aiipworld.com/v1/pdf-jobs with op pdf_unlock, the password and the upload id, and poll GET /v1/jobs/:id.
- Free without an account: 20 PDF jobs per day per visitor, no watermark. Signed in, each job costs 1 credit, plus 1 credit for each started 20 MB of result beyond the first 20 MB (100 free credits every month); a wrong password or a file that is not protected is refunded.
- Files are deleted automatically: 10 minutes after conversion without an account, 1 day with a free account.

## How it works

1. Choose the password-protected PDF you want to unlock. Use only a file you own or have the right to open.
2. Type the password that opens the file, or its owner password. Case matters and spaces count. You can tick "Show the password" to check what you typed.
3. Leave "Repair a slightly damaged PDF automatically" on, or switch it off if you want damaged files refused instead.
4. Run the job, then download unlocked.pdf. Your original file is not changed.

## How to remove password from PDF, step by step

To remove password from PDF files with this page, you need the password that opens the file. Upload the PDF, type that password, and run the job. The tool returns a new PDF named unlocked.pdf with no password and no permission limits.

A pdf unlock keeps the content: pages, text, pictures, bookmarks and form fields are kept, and the page count stays the same. If a job fails, the result panel or the message tells you why.

## Which password Unlock PDF needs

For a pdf unlock to work, you need one of two kinds of password. The user password, also called the open password, is the one that opens the file. The owner password also works, and it also removes permission limits.

A PDF that opens without a password but blocks printing, copying or editing needs its owner password to remove those limits. The user cannot remove them without it.

- The password that opens the file: works for the unlock.
- The owner password: works, and removes permission limits too.

## Unlock PDF does not crack, guess or recover passwords

Unlock PDF uses only the one password you type for each job. It does not crack, guess, search for or recover passwords, and it does not try variations of the password you give.

If you do not know the password, the tool cannot open the file, and we cannot help you open it. The tool is meant for files you own or have the right to open. Using it to get around protection that someone else set on a file is not allowed under our Acceptable Use Policy.

## PDFs that only limit printing, copying or editing

Some PDFs open without any password but switch off printing, copying or editing. These are permission limits, and removing them needs the owner password. If you give a wrong password for such a file, the message says: "This PDF opens without a password but limits printing, copying or editing, and removing those limits needs its owner password."

A PDF with no password and no limits gets a different message: "This PDF is not password-protected, so there is nothing to unlock." No credits are used in that case.

## What you get: no password and no limits

The result is a new PDF with no password and no permission limits. The result panel shows the encryption the file had (AES-256, AES-128, RC4-128 or RC4-40), which password was used, whether limits were removed, the page count, the size and the credits used.

In our tests we used a generated 6 page handbook of 51 KB with invented text. Protected with AES-256, it became 53 KB. Unlocked with the user password, it became a 52 KB PDF with 6 pages that reports Encrypted: no, and it kept the same text of 1409 characters. These were generated test files, not real documents, so results vary with the file.

## Digital signatures: what can stop working

Removing protection changes the file, so a digital signature in the PDF can become invalid. We do not keep signatures valid. Check the signature in the result if it matters for your use.

Your original file is not changed by the tool. Keep it if you need the signed version for a record or for a later check.

## What happens to your password

Your password is sent to our server over HTTPS and is used only for this one job. While the job waits in the queue, it is kept only in encrypted form. It is never written to the database or the logs, and it is not in the result.

The password is deleted when the job ends. The code box on this page never shows a password you typed; it shows YOUR_PDF_PASSWORD instead. The uploaded file is sent to our server, and the working copy is deleted as soon as the job ends, whether it succeeds or fails.

## Wrong passwords: why a file can be refused for a while

The tool tries only the one password you give for each job. It does not retry or try variations such as other upper or lower case, extra spaces or added characters. Each wrong password counts toward a limit on that file.

After 10 wrong passwords for the same file within 24 hours, every further attempt on that file is refused with "Too many wrong passwords were tried for this file". This applies even with the right password, until the time passes. A different file is not affected. In our test, the 11th attempt on one file was refused, including the correct password.

## Limits: size, pages and credits

- PDF size: one PDF, up to 10 MB without an account and up to 50 MB signed in.
- Pages: up to 100 pages without an account and up to 500 pages signed in.
- Daily jobs: 20 PDF jobs per day per visitor, shared with the other PDF tools on this site.
- Uploads: without an account, each uploaded file has its own human check (Cloudflare Turnstile) and counts toward 40 uploads per day per visitor.
- Credits: signed-in jobs use 1 credit, plus 1 credit for each started 20 MB of the result beyond the first 20 MB. Prices are provisional. You get 100 free credits every month.
- Passwords: 1 to 127 bytes in UTF-8, so accented and non-Latin letters work.
- Results are kept for 10 minutes in the free web tool, and download links are short-lived.

## Unlock a PDF from code

To unlock a PDF through the API, first send the raw file bytes to https://api.aiipworld.com/v1/uploads with the Content-Type application/pdf. Send one file per request. The answer includes an upload_id.

Then send a POST to https://api.aiipworld.com/v1/pdf-jobs with JSON that contains op set to pdf_unlock, params with password (required, 1 to 127 bytes) and allow_repair, and files set to the upload_id. Poll GET /v1/jobs/:id until the job succeeds, fails or times out. The result includes unlocked, encryption, password_type, restrictions_removed and pages, and download_url is a short-lived signed link.

Authorize with Authorization: Bearer `<API key>` or x-api-key. Errors include 400 invalid_params, 413 file_too_large, 402 insufficient_credits, 429 rate limited, 422 not_a_pdf and 404 upload_not_found. A failed job can return error codes such as wrong_password, not_encrypted, unsupported_encryption, too_many_attempts, corrupt_pdf, bad_params and too_many_pages. The page shows a ready cURL, Node and Python example built from your settings, and those examples use YOUR_PDF_PASSWORD. See /docs/ for the general API.

## Questions

### Can I unlock a PDF for free?

Yes, you can use the free web tool without an account, within the daily limits. Each uploaded file needs a human check and counts toward 40 uploads per day per visitor. Signed-in users use credits, and 100 free credits come every month.

### How do I remove a password from a PDF?

Enter the password that opens the file, or its owner password, then run the job and download unlocked.pdf. As a pdf password remover it only works when you know the password. The original file is not changed.

### Can you unlock a PDF if I forgot the password?

No. The tool needs the password you type and does not crack, guess, search for or recover passwords. If you do not know the password, the tool cannot open the file, and we cannot help.

### Do I need the owner password or the user password?

The user password opens a file that needs a password to open, and the owner password works for that file too. The owner password is the one you need to remove printing, copying and editing limits on a file that opens without a password.

### Why does the tool say my PDF is not password-protected?

The file has no password and no permission limits, so there is nothing to unlock. No credits are used. You can use the file as it is.

### Why was my file refused after wrong passwords?

After 10 wrong passwords for the same file within 24 hours, further attempts on that file are refused for a while. The refusal applies even to the right password, and a different file is not affected.

### Can I unlock a PDF that has a digital signature?

You can run the unlock, but the signature can become invalid because removing protection changes the file. We do not keep signatures valid, so keep your original file.

### Is my password stored?

Your password is sent over HTTPS, used only for that one job, and never written to the database or the logs. It is kept only in encrypted form while the job waits, and it is deleted when the job ends.

### Which kinds of PDF protection can the tool open?

The tool supports user passwords, owner passwords, RC4 40-bit, RC4 128-bit, AES-128 and AES-256. It does not support encryption with a certificate (public-key encryption), and that job fails with a message that says so.

### Can I unlock a PDF in my own code?

Yes, with the API and the op pdf_unlock. Upload the file to /v1/uploads, send a job to /v1/pdf-jobs with the password parameter, and poll the job until it finishes. The page shows ready examples with YOUR_PDF_PASSWORD.

## Related

- [Password Protect PDF](https://aiipworld.com/tools/protect-pdf/index.md)
- [Merge PDF Files Online for Free](https://aiipworld.com/tools/merge-pdf/index.md)
- [Split PDF Online, Free](https://aiipworld.com/tools/split-pdf/index.md)
- [Rotate PDF Online for Free](https://aiipworld.com/tools/rotate-pdf/index.md)
- [Flatten PDF](https://aiipworld.com/tools/flatten-pdf/index.md)
- [Resize PDF](https://aiipworld.com/tools/resize-pdf/index.md)

Page: https://aiipworld.com/tools/unlock-pdf/