JWT Algorithms·7 min read·2026-02-25T14:00:00Z

HS256 vs HS384 vs HS512: Architectural Comparison and Benchmark Guide

Choosing among HS256, HS384, and HS512 requires balancing security margins with HTTP header payload size. Here is an objective comparison to help you choose the right algorithm for your infrastructure.

Direct Comparison Matrix

| Feature | HS256 | HS384 | HS512 | | :--- | :--- | :--- | :--- | | **Hash Algorithm** | SHA-256 | SHA-384 | SHA-512 | | **Minimum Key Size** | 256 bits (32 B) | 384 bits (48 B) | 512 bits (64 B) | | **Signature Size** | 32 bytes (43 Base64 chars) | 48 bytes (64 Base64 chars) | 64 bytes (86 Base64 chars) | | **Quantum Collision Margin** | 128 bits | 192 bits | 256 bits | | **Recommended For** | General Web & Mobile Apps | Enterprise & Compliance | Maximum Long-term Security |

Frequently Asked Questions

Which algorithm is best for mobile APIs?

HS256 is generally preferred for mobile APIs because its 43-character signature minimizes HTTP header overhead on cellular connections while providing formidable security.

HS256 vs HS384 vs HS512 – Which HMAC Algorithm Should You Use? | مولد مفتاح JWT السري | JWT Secret Key Generator