Both are open source. Both have devoted user bases. The fundamental architectural difference: KeePass is a local .kdbx file you bring-your-own-sync; Bitwarden is a cloud service (or self-hosted server) with multi-device sync built in.
| Bitwarden | KeePass | |
|---|---|---|
| Architecture | Cloud sync (or self-host server) | Local .kdbx file |
| Cost | Free / $10 Premium | Completely free, no tiers |
| Open source | Yes | Yes (longest history — since 2003) |
| Browser autofill | First-party extension | Third-party (KeePassXC-Browser, KeeWeb) |
| Mobile autofill | Native iOS / Android apps with full integration | Third-party apps (Keepass2Android, KeePassium, Strongbox) |
| Multi-device sync | Built-in | BYO sync (Dropbox, syncthing, Nextcloud, OneDrive) |
| Encryption | AES-256-CBC + PBKDF2/Argon2id | AES-256, ChaCha20 + Argon2 (KDBX 4) |
| Sharing | Organisations / Collections | None (or via shared file) |
| Web access | vault.bitwarden.com | None (file-based only) |
| Audit history | Cure53 2018, 2020 | BSI audit (2014, German federal) |
| Native client (official) | Yes — all platforms | Windows-only (KeePass 2 .NET) |
| Cross-platform clients | One codebase across all | Multiple ports — KeePassXC, KeeWeb, MacPass |
The fundamental disagreement: do you trust any cloud service with your encrypted vault?
KeePass purists say no — even encrypted ciphertext on a third-party server is a target. The .kdbx file lives on your machine. You sync it via whatever you trust (your own Nextcloud, syncthing peer-to-peer, Dropbox if you don't care, USB stick if you really don't trust anything).
Bitwarden's response: with strong encryption (AES-256, PBKDF2 600K iterations), the ciphertext is useless to an attacker. The convenience of automatic sync is worth far more than the marginal security gain of avoiding cloud storage. And if you truly don't want any third party involved, self-host Bitwarden.
Both positions are defensible. Pick based on your actual threat model and patience for sync friction.
KeePass family relies on third-party browser integration (KeePassXC-Browser plugin connects KeePassXC to Chrome/Firefox via native messaging). It works, but the setup is non-obvious — install KeePassXC, install KeePassXC-Browser, pair them via a one-time secret, manage the connection.
Bitwarden has a first-party browser extension. Install, sign in, autofill works. The UX gap is significant for non-technical users.
Mobile is similar: Bitwarden has official iOS and Android apps with system-level autofill integration. KeePass family relies on third-party apps (Keepass2Android, KeePassium, Strongbox) — they're good, but it's third-party software you're trusting.
KeePass's killer feature is the .kdbx file format itself. It's:
Bitwarden's vault is JSON-encrypted, exportable, but the format is less of a portable artefact. If you're a "I want my data in a single file I can hold" person, KeePass wins.
Both excellent. KDBX 4 supports AES-256 or ChaCha20 plus Argon2 KDF (the modern recommendation). Bitwarden uses AES-256-CBC plus PBKDF2 600K or Argon2id.
KeePass historically supported the broadest cipher options (Twofish, Serpent, ChaCha20 alongside AES). Bitwarden is more standardised. For 99% of threat models, both are equivalent.
Bitwarden's importer handles standard KDBX fields well. Custom fields and entry icons may not migrate cleanly — minor annoyance, not blocking.
Some users do — Bitwarden for daily-use credentials (email, banking, work logins), KeePass for high-paranoia long-term storage (recovery seeds for crypto wallets, BitLocker keys, root account credentials). The KeePass file lives on a USB stick, never online; Bitwarden handles 99% of daily authentication.
Defensible setup. Adds maintenance overhead but explicit threat-model separation.
KeePass is the local-file purist; the rest of the field sits on different points along the cloud-sync trade-off. If you're weighing more than two options, see how Bitwarden stacks against the polished commercial competitors:
"Safer" depends on threat model. KeePass's offline file removes one attack surface (cloud breach) but adds another (your file lives on your machine — easier for an attacker who already has machine access). Both are very secure with strong master passwords. The difference is more about who you fear: a server-side breach vs an endpoint attacker.
The original KeePass 2 is Windows-only (.NET). Other developers wrote ports for other platforms: KeePassXC (cross-platform Qt), MacPass (macOS native), KeePassDX (Android), Keepass2Android (Android), KeePassium (iOS), Strongbox (iOS), KeeWeb (web/Electron). They all read/write the same .kdbx format. Fragmented but interoperable.
Yes — put the .kdbx file in Dropbox / OneDrive / Google Drive / Nextcloud / syncthing / iCloud, sync runs automatically. KeePass on each device opens the file from the synced folder. Conflict resolution if two devices edit simultaneously — generally handled by sync provider, not always cleanly.
Yes — Bitwarden web vault can import KeePass 2 XML format. Direct .kdbx import isn't supported (requires master password to decrypt), but XML export from KeePass then import to Bitwarden works.
Sure — different vaults for different purposes. Common setup: Bitwarden for everyday credentials, KeePass on a USB stick for cold-storage long-term secrets (crypto seeds, recovery codes, etc.). Adds complexity but legitimate threat-model separation.
KeePassXC is a cross-platform fork of the original KeePass 2 — same .kdbx format, similar UX, but Qt-based instead of .NET. KeePassXC has a more active development pace and better Linux/Mac support. For all practical purposes, KeePassXC is what most users mean when they say "KeePass" in 2026.