The best free alternative to Spideroak One Backup is MEGA. If that doesn't suit you, our users have ranked more than 100 alternatives to Spideroak One Backup and loads of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to Spideroak One Backup are ownCloud (Freemium, Open Source), Duplicati (Free, Open Source), IPFS (Free, Open Source) and pCloud (Freemium).
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