Bcrypt vs Argon2: Password Hashing Comparison

Compare Bcrypt and Argon2 password hashing algorithms. Learn which provides better security, performance, and resistance to GPU and ASIC attacks.

Item 1

Bcrypt

A password-hashing function based on the Blowfish cipher. Widely adopted with configurable cost factor. The most common legacy choice for password storage.

Try it free

Widely adopted and battle-tested in production
Built-in salt generation
Configurable cost factor for future-proofing
Available in every major language and framework
Simple API with minimal configuration

Item 2

Argon2

The winner of the 2015 Password Hashing Competition. Designed specifically for password hashing with configurable memory, time, and parallelism costs.

Try it free

Resistant to GPU/ASIC/FPGA attacks by design
Three configurable dimensions: memory, time, parallelism
Winner of the PHC — modern gold standard
Better resistance to side-channel attacks
Future-proof design with tunable parameters

Side-by-Side Comparison

Aspect	Bcrypt	Argon2	Winner
GPU resistance	CPU-bound only — vulnerable to GPU arrays	Memory-hard — resists GPU/ASIC attacks effectively	Argon2
Configurability	Single cost factor (rounds)	Three dimensions: memory, time, parallelism	Argon2
Adoption	Available in every language and framework	Available but less ubiquitous than bcrypt	Bcrypt
Standing	Industry standard for 20+ years	PHC winner (2015) — modern gold standard	Argon2
Output size	Fixed 60-character string	Variable length configurable output	Bcrypt

Verdict

Use Argon2id for new applications — it is the modern gold standard with resistance to GPU/ASIC attacks. Use Bcrypt if you need maximum compatibility across older systems or simpler configuration.

Recommended: Argon2 (new projects), Bcrypt (compatibility)

Frequently Asked Questions

Should I migrate from bcrypt to Argon2?

If you are starting a new project, use Argon2id. For existing bcrypt hashes, migration is complex — typically done by re-hashing on next login.

Is Argon2 harder to configure than bcrypt?

Argon2 has more parameters but reasonable defaults exist. The Argon2id variant with recommended parameters is as easy as bcrypt.

Bcrypt vs Argon2: Password Hashing Comparison

Compare Bcrypt and Argon2 password hashing algorithms. Learn which provides better security, performance, and resistance to GPU and ASIC attacks.

Item 1

Bcrypt

A password-hashing function based on the Blowfish cipher. Widely adopted with configurable cost factor. The most common legacy choice for password storage.

Try it free

Widely adopted and battle-tested in production
Built-in salt generation
Configurable cost factor for future-proofing
Available in every major language and framework
Simple API with minimal configuration

Item 2

Argon2

The winner of the 2015 Password Hashing Competition. Designed specifically for password hashing with configurable memory, time, and parallelism costs.

Try it free

Resistant to GPU/ASIC/FPGA attacks by design
Three configurable dimensions: memory, time, parallelism
Winner of the PHC — modern gold standard
Better resistance to side-channel attacks
Future-proof design with tunable parameters

Side-by-Side Comparison

Aspect	Bcrypt	Argon2	Winner
GPU resistance	CPU-bound only — vulnerable to GPU arrays	Memory-hard — resists GPU/ASIC attacks effectively	Argon2
Configurability	Single cost factor (rounds)	Three dimensions: memory, time, parallelism	Argon2
Adoption	Available in every language and framework	Available but less ubiquitous than bcrypt	Bcrypt
Standing	Industry standard for 20+ years	PHC winner (2015) — modern gold standard	Argon2
Output size	Fixed 60-character string	Variable length configurable output	Bcrypt

Verdict

Use Argon2id for new applications — it is the modern gold standard with resistance to GPU/ASIC attacks. Use Bcrypt if you need maximum compatibility across older systems or simpler configuration.

Recommended: Argon2 (new projects), Bcrypt (compatibility)

Frequently Asked Questions

Should I migrate from bcrypt to Argon2?

If you are starting a new project, use Argon2id. For existing bcrypt hashes, migration is complex — typically done by re-hashing on next login.

Is Argon2 harder to configure than bcrypt?

Argon2 has more parameters but reasonable defaults exist. The Argon2id variant with recommended parameters is as easy as bcrypt.