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Q & A Developer · September 11, 2026

What is the difference between MD5 and SHA-1?

MD5 (128 bits) predates SHA-1 (160 bits). Both are cryptographically broken — MD5 collisions since 2004, SHA-1 collisions demonstrated by Google in 2017 (SHAttered attack). Neither should be used for security-sensitive purposes. SHA-1 held longer than MD5 but both are now retired for signatures, TLS certs, and integrity of untrusted data. Modern default: SHA-256 or SHA-512. For non-security uses (file checksums against accidental corruption, de-duplication keys), MD5 or SHA-1 remain acceptable. Generate all four with the hash generator.

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What Is a JWT?
JWT (JSON Web Token) is the dominant format for API authentication, OAuth access tokens, and stateless session management. Three base64-encoded segments carry the header, claims, and signature — anyone can read them, but only the key holder can produce a valid token.
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