Create or open a .cocosigncert file — the same certificate bundle format Cocosign imports and exports on your phone, from your browser instead.
Package a .p12 and provisioning profile(s) into a .cocosigncert file, optionally encrypted with a passphrase.
Extract the .p12 and provisioning profile(s) back out of a .cocosigncert file, as a .zip you download — includes a password.txt with the .p12's own password, if it has one.
Heads up: this tool is new. If a bundle created here won't open in Cocosign, or one exported from Cocosign won't open here, please report it on Discord so it can get fixed — don't rely on it as your only backup of an important certificate yet.