How does encryption work?
Clipo offers two kinds of encryption. Files that use either one show a 🔒 note on their share page.
End-to-end encryption (web uploads)
Switch on End-to-end encrypt before uploading on the website. Your browser then:
- creates a brand-new random 256-bit key for that file,
- encrypts the file (and its name and type) with AES-256-GCM in 1 MiB pieces, and
- uploads only the scrambled bytes. The server knows just the size and a broad category (image, video, document…) so it can show the right icon.
The key is added to the share link after the #, for example https://clipo.do/aB3dE9#Xy7…. Browsers never send the part after # to a server, so we never receive the key and cannot open your file. Not our staff, not someone with access to the server or the storage bucket.
When someone opens the full link, their browser downloads the scrambled bytes and decrypts them on their own device.
Good to know:
- Keep the full link. If you lose it we can't recover the key, and the file can't be opened. This browser also remembers the keys for files you uploaded from it, so your dashboard can show their names.
- Anyone with the full link can open the file. Add a password too if the link might leak.
- Link previews on Discord, X and similar apps show Encrypted file instead of a thumbnail, because nobody but the link holder can see the contents.
- Very large files are decrypted in memory, so a phone may struggle with multi-gigabyte videos.
Encryption at rest (apps, ShareX and the API)
Tools such as ShareX can't encrypt in advance, so their uploads can be encrypted by the server instead. The server encrypts the file with AES-256-GCM using a per-file key before writing it to storage. That key is itself locked with a master key that never leaves this installation. Thumbnails are encrypted the same way.
This protects against someone who gets hold of the raw storage (a disk, a backup or an S3 bucket). Because the server decrypts the file to show it to visitors, anyone with the link can still open it.
Passwords and expiry
Any file, short link or paste can be password-protected and given an expiry date. Expired items are deleted permanently.
Unlisted by default
There is no public feed or search. Links are random codes that nobody can guess or enumerate.
Deleting
Deleting a file removes it from storage immediately, including its thumbnail. Deleting your account deletes everything you uploaded.