D63af914bd1b6210c358e145d61a8abc

It could be part of a UUID version 3 or 5 (which use MD5 or SHA-1), or a truncated SHA-1.

| Property | Why It Matters | |----------|----------------| | Deterministic | Same input always yields the same hash. | | Pre‑image resistance | Given a hash, it is computationally infeasible to find an input that produces it. | | Second‑pre‑image resistance | Hard to find a different input that hashes to the same value as a known input. | | Collision resistance | Finding any two distinct inputs that produce the same hash is extremely difficult. | | Avalanche effect | Changing a single bit of the input drastically changes the output hash. |

String: D63af914bd1b6210c358e145d61a8abc
Length: 32 characters
Character set: 0–9, a–f (hexadecimal lowercase) D63af914bd1b6210c358e145d61a8abc

MD5 hashes are always 32 hex characters (128 bits). This matches perfectly.

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If you control the system generating such hashes, consider migrating to: It could be part of a UUID version

| Algorithm | Output length | Security | |-----------|--------------|----------| | SHA-256 | 64 hex chars | Strong | | SHA-3 | variable | Strong | | bcrypt | 60 chars | Password-friendly | | UUID v4 | 36 chars | Random identifier (not hash) |

The security of any identifier depends on how it is generated and used. If you control the system generating such hashes,

| Aspect | Assessment for this format | |--------|----------------------------| | Entropy | 128 bits – excellent. | | Predictability | If generated via MD5 of predictable data (e.g., "user1"), it’s insecure. If random, secure. | | Length | Sufficient to resist brute-force enumeration. | | Algorithm | MD5 (if applicable) is broken for collision attacks but still fine for non-cryptographic uses like indexing. |

Critical warning: Do not use MD5 hashes for storing passwords, digital signatures, or certificates. Use bcrypt, Argon2, or PBKDF2 instead.

CREATE TABLE records (
    id CHAR(32) PRIMARY KEY,
    data TEXT
);
INSERT INTO records (id, data) VALUES ('d63af914bd1b6210c358e145d61a8abc', 'Sample content');

Without cryptographic reversing (not possible by design), the original could be:

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