Both extensions save and auto-fill passwords, generate strong new ones and sync your vault across devices. Bitwarden stands out for being open-source with a generous free tier, while LastPass offers a comparable experience with a more restricted free plan and a closed codebase.
Free plan features compared
Bitwarden's free plan includes unlimited passwords and syncing across unlimited devices, which is unusually generous for a password manager. LastPass's free plan has previously restricted syncing to one device type at a time, making Bitwarden the stronger option if you want a fully free experience across phone and desktop.
Open-source vs closed-source security
Bitwarden is open-source, meaning its code is publicly available for security researchers to review, which adds a layer of transparency. LastPass is closed-source, so its internal code isn't publicly auditable in the same way, though it still uses standard encryption to protect stored passwords.
Auto-fill and password generation
Both extensions auto-fill saved logins on websites and include a password generator for creating strong, random passwords. The core day-to-day experience is similar between them, so the bigger differences show up in pricing, security philosophy and the extra features on paid plans.