Email is a postcard: every server between you and the recipient can read it. When the attachment is a contract, a payslip, or medical records, that matters — and 'please delete after reading' is not a security policy. The Protect PDF card wraps your document in AES-256 encryption, the same cipher banks use, so anyone without the password gets a locked door instead of your data.
Two passwords, two different jobs
PDF security has two layers and they confuse everyone. The user (open) password gates the whole file — no password, no content. The owner (permissions) password allows opening but restricts printing, copying, and editing. For sending a payslip, set a strong open password and share it through a different channel than the file itself (text the password, email the PDF — never both together). For a price list, skip the open password and use permissions only, so anyone can read but nobody can copy-paste your numbers. Our security architecture explains exactly how keys are handled: encryption happens server-side in memory, and nothing persists after your download.
Passwords are a beginning, not a plan
Be honest about the threat model: a password stops casual snooping and forwarding accidents, not a determined attacker with the file — so pair it with minimal exposure. Split PDF first and send only the pages the recipient needs; fewer pages means less blast radius. Need the file back in editable form later? Unlock PDF removes protection you own the rights to, and Repair PDF salvages files damaged in transit. And never reuse your email password as a document password — document passwords get shared by design.