May 20, 2026 · 6 min read
Crypt12 vs Crypt14 vs Crypt15 explained
WhatsApp has shipped four backup formats over the last decade. Most modern phones produce Crypt15, but the older formats still turn up in old phones and rescued storage. What each one is and what's supported by what.
crypt12crypt14crypt15whatsapp formats
Every so often a customer email lands with 'I have msgstore.db.crypt12, can your app read it?'. The answer is no, today, and the underlying reason is interesting: WhatsApp's backup format reflects what kind of encryption the platform supported at the time.
Five-year timeline
- Crypt5–Crypt9: very old WhatsApp versions, AES-CBC plus various wrapping schemes. Long since unused.
- Crypt12 (2017–2019 era): AES-GCM under a server-derived key tied to your phone number. Backups could be decrypted with WhatsApp's cooperation, or with the leaked server-side key in some forums.
- Crypt14 (2019–2021): same family as Crypt12, slightly different header, still server-derived key.
- Crypt15 (October 2021 → today): fully end-to-end encrypted backup. The key never leaves your device. AES-256-GCM with the 32-byte root key WhatsApp shows you as 64 hex digits.
How to tell which one you have
Look at the filename suffix: msgstore.db.crypt15 → Crypt15. msgstore.db.crypt14 → Crypt14. Same logic for crypt12. If you've got a file with no suffix, it was likely renamed by hand; you can inspect the header bytes with a hex editor: Crypt15 starts with a protobuf varint (often 0x0A), Crypt14 begins differently (a fixed header structure including IV and key version).
What Chat Hoarding supports today
Crypt15 only. Crypt12 and Crypt14 are not on the roadmap as first-class formats: they have a different security model (server-derived key), and pre-E2EE backups are increasingly rare in 2026.
How to upgrade an old backup to Crypt15
- 01Install the latest WhatsApp on an Android device with your number.
- 02Tap Restore from the old backup file (WhatsApp can read older formats if they belong to the account).
- 03Once the messages are restored, go to Settings → Chats → Chat backup → End-to-end encrypted backup → On.
- 04Generate a 64-digit key. Save it.
- 05Tap Back Up Now. The new backup is Crypt15, decryptable by Chat Hoarding for Mac.
FAQ
Can I convert Crypt14 to Crypt15 offline?
Not really. You can decrypt a Crypt14 file with the right server-side key using open-source tools (wa-crypt-tools supports them), but the resulting msgstore.db is a different schema generation than what modern Chat Hoarding expects. The supported path is restore-on-phone then re-backup as Crypt15.
Does Crypt15 mean Meta can no longer access my backup?
Correct. The 64-digit key never leaves your device. Meta's server holds the encrypted blob; without the key, the blob is just bytes. This is also why losing the key means losing the backup forever.