Syncthing.

Open-source continuous file synchronisation without a central server

Facts

Cozy Cloud
French personal cloud platform for storage, contacts and finances
FR · open-source
↗
Ente
Encrypted photo storage and backup as Google Photos alternative
NL · open-source
↗
Filen
German zero-knowledge encrypted cloud storage with high security
DE · open-source
↗
Internxt
Spanish privacy cloud storage with zero-knowledge encryption
ES · open-source
↗
Jottacloud
Norwegian cloud backup and storage
NO · commercial
↗
kDrive (Infomaniak)
Swiss cloud storage by Infomaniak with office suite and collaboration
CH · commercial
↗
Koofr
Slovenian cloud storage with end-to-end encryption and multi-cloud connection
SI · commercial
↗
luckycloud
German cloud storage service with servers exclusively in Germany
DE · commercial
↗