Is my file uploaded to be encrypted?

It is not. The bytes are read into this tab, encrypted by your browser's own cryptography engine and handed straight back as a download. Disconnect from the network before you start if you want to watch that claim hold up.

How big a file can this handle?

512 MB is the stated limit. The whole file and its encrypted copy are both held in memory at once, so a device with little RAM will struggle before that. For very large archives, split them first or use a desktop tool built for streaming.

What happens if I forget the password?

The file is unrecoverable. That is not a support policy that could be appealed — there is no account, no stored key and no copy of anything on our side. Treat the password as the file.

Can the recipient open it without visiting this site?

Not conveniently. The container is specific to these tools, so the intended route is the matching decrypt page, which also runs entirely in their browser. If the recipient needs a standard format, use GPG or an encrypted archive instead.

Does encrypting hide the filename and size?

The size is still visible, and the name is too unless you switch off the option that preserves the extension. Encryption conceals contents, not metadata. If the existence or the size of the document is the sensitive part, put it inside an archive with other files first.

Encrypt File

Password-protect any file with AES-256-GCM before you send it.

Everything runs inside your browser. Your files never leave your device.

Drop your files here

· they stay on this device

Ask about Encrypt File

Questions about what this tool does, which option to pick, or what it can and cannot handle.

The question you type here is sent to an AI provider to be answered — your files and whatever you put in the tool above are not, and the assistant cannot see them. Answers are generated and can be wrong. The tool itself is not guessing: it runs deterministic code on your device.

About the Encrypt File

Cloud storage, email attachments and messaging apps all read what passes through them, whatever their marketing says about privacy. Encrypting a file before it goes into any of them changes what they are holding: not your document, but an opaque block that means nothing without your password.

The tool takes any file — a PDF, a spreadsheet, a photograph, an archive, a video — and seals it with AES-256-GCM. The key comes from your password through PBKDF2 at 600,000 rounds, so a weak password is still a weak password, but a good one is genuinely expensive to attack. The result is a “.enc” file you download as normal and can put anywhere.

Two design choices are worth knowing about. First, the original filename keeps its extension inside the new name, so “accounts.xlsx” becomes “accounts.xlsx.enc” and whoever decrypts it gets a spreadsheet back rather than an anonymous blob. If the file type is itself sensitive, there is a switch to drop it. Second, the whole file is encrypted as one unit rather than in chunks. Chunking would allow arbitrarily large files, but it would also mean inventing a chunk format, and home-made chunk formats are historically where encryption goes wrong. The honest trade is a stated 512 MB ceiling instead of a subtle weakness.

Because GCM authenticates as well as encrypts, decryption doubles as an integrity check. A file that comes back is a file that has not been altered by anything since it was sealed — not by a flaky transfer, not by a storage provider, not by anyone in between. If it has been altered, it refuses to open rather than handing you a damaged document.

How to use it

1Drop in the files you want to protect. Any type works, and you can do several at once with the same password.
2Enter a password, then enter it again in the confirmation field. There is no recovery, so a typo would be permanent.
3Adjust the PBKDF2 rounds only if you have a reason. Higher is slower for an attacker and for you in equal measure.
4Press the button and wait — key derivation is meant to be slow, so a second or two of work is the tool functioning correctly.
5Download the .enc files, and put the password in a password manager before you close the tab.

Questions

Is my file uploaded to be encrypted?: It is not. The bytes are read into this tab, encrypted by your browser's own cryptography engine and handed straight back as a download. Disconnect from the network before you start if you want to watch that claim hold up.
How big a file can this handle?: 512 MB is the stated limit. The whole file and its encrypted copy are both held in memory at once, so a device with little RAM will struggle before that. For very large archives, split them first or use a desktop tool built for streaming.
What happens if I forget the password?: The file is unrecoverable. That is not a support policy that could be appealed — there is no account, no stored key and no copy of anything on our side. Treat the password as the file.
Can the recipient open it without visiting this site?: Not conveniently. The container is specific to these tools, so the intended route is the matching decrypt page, which also runs entirely in their browser. If the recipient needs a standard format, use GPG or an encrypted archive instead.
Does encrypting hide the filename and size?: The size is still visible, and the name is too unless you switch off the option that preserves the extension. Encryption conceals contents, not metadata. If the existence or the size of the document is the sensitive part, put it inside an archive with other files first.