Need · Protect
密碼產生器
在瀏覽器本機產生高強度的隨機密碼——任何內容都不會傳送到伺服器。
一個結實的密碼，在這裡產生，哪裡也不去。— Poulpi
Strength129 bits
Generated with crypto.getRandomValues, locally: the password never leaves your device.
在瀏覽器本機產生高強度的隨機密碼——任何內容都不會傳送到伺服器。
一個結實的密碼，在這裡產生，哪裡也不去。— Poulpi
The best encryption in the world is worthless behind a guessable password. When you lock a confidential PDF with the protect tool before sending it — a payslip, a contract, a medical file, a bank statement — that password carries the entire security of the file. Yet the ones we invent nearly all follow the same patterns: a first name, a birth date, a company name, a capital at the start, an exclamation mark at the end, a few letters swapped for digits. Dictionary attacks know those rules by heart and get through them in seconds.
The other reason is reuse. A unique password per service is the only effective defence against credential stuffing: when a site is breached, the stolen credentials are immediately tried on mailboxes, banks and social networks. A different password everywhere confines the leak to a single account — but nobody can memorise fifty of them, hence the point of drawing a random one each time and handing it to a password manager.
The generator relies on crypto.getRandomValues, the browser's built-in cryptographic random number generator, rather than the Math.random used by many scripts, whose sequence is predictable. Every character is drawn without bias: values that would fall outside an exact multiple of the character set size are rejected and redrawn, so no character is more likely to come up than another. You set the length and the character sets, and the entropy is displayed in bits to tell you objectively how strong the result is. Everything is computed locally: nothing is ever transmitted, nothing is recorded, no history is kept.
Aim for at least 80 bits of entropy for everyday use, and more for a document you keep for years. Store the password in a manager rather than a text file, and above all send it through a different channel from the document itself: the PDF by e-mail, the password by phone or messaging app. Once the password is generated, the protect tool encrypts the file, and the unlock tool removes a protection whose password you already have. Here, everything happens in your browser: nothing is sent to our servers.
上傳
將您的 PDF 檔案上傳至拖放區（或直接拖曳放入）。
設定
在瀏覽器本機產生高強度的隨機密碼——任何內容都不會傳送到伺服器。
下載
一鍵下載處理後的文件——您的檔案在處理完成後會自動刪除。