Is a sha512crypt ($6$) hash reversible?

No. sha512crypt ($6$) is a one-way hash; you cannot reverse it. You can only guess inputs and compare, which is what hashcat and John do.

What is the hashcat mode for sha512crypt ($6$)?

Use `-m 1800` to tell hashcat to treat the input as sha512crypt ($6$).

How long does it take to crack sha512crypt ($6$)?

sha512crypt ($6$) is intentionally slow, so brute force is impractical — success depends on the password appearing in your wordlist.

Is a sha512crypt ($6$) hash reversible?

No. sha512crypt ($6$) is a one-way hash; you cannot reverse it. You can only guess inputs and compare, which is what hashcat and John do.

What is the hashcat mode for sha512crypt ($6$)?

Use `-m 1800` to tell hashcat to treat the input as sha512crypt ($6$).

How long does it take to crack sha512crypt ($6$)?

sha512crypt ($6$) is intentionally slow, so brute force is impractical — success depends on the password appearing in your wordlist.

How to identify and crack a sha512crypt ($6$) hash

sha512crypt ($6$) is a unix crypt hash type. It uses a deliberately slow, salted key-derivation scheme, so only weak or short passwords are realistically recoverable. This page shows how to recognise it and the exact commands to attack it.

All identification runs locally in WebAssembly. The commands below write the hash to a local file on your machine — nothing is sent to this site.

Identifying the hash

The hash identifier on the home page detects sha512crypt ($6$) entirely in your browser — your hash is never uploaded. A typical example looks like this:

$6$52450745$k5ka2p8bFuSmoVT1tzOyyuaREkkKBcCNqoDKzYiJL9RaE8yMnPgh2XzzF0NDrUhgrcLwg78xs1w5pJiypEdFX/

Cracking sha512crypt ($6$) with hashcat

Save the hash to a file and run hashcat in mode -m 1800. Expect this to be slow — use a focused wordlist. Start with a wordlist such as rockyou.txt:

echo '$6$52450745$k5ka2p8bFuSmoVT1tzOyyuaREkkKBcCNqoDKzYiJL9RaE8yMnPgh2XzzF0NDrUhgrcLwg78xs1w5pJiypEdFX/' > hash.txt && hashcat -m 1800 hash.txt /usr/share/wordlists/rockyou.txt

Add a rule set to mutate dictionary words (capitalisation, leetspeak, appended digits) and dramatically widen coverage:

echo '$6$52450745$k5ka2p8bFuSmoVT1tzOyyuaREkkKBcCNqoDKzYiJL9RaE8yMnPgh2XzzF0NDrUhgrcLwg78xs1w5pJiypEdFX/' > hash.txt && hashcat -m 1800 hash.txt /usr/share/wordlists/rockyou.txt -r /usr/share/hashcat/rules/best64.rule

Cracking sha512crypt ($6$) with John the Ripper

John the Ripper can attack the same hash with the sha512crypt format:

echo '$6$52450745$k5ka2p8bFuSmoVT1tzOyyuaREkkKBcCNqoDKzYiJL9RaE8yMnPgh2XzzF0NDrUhgrcLwg78xs1w5pJiypEdFX/' > hash.txt && john --format=sha512crypt --wordlist=/usr/share/wordlists/rockyou.txt hash.txt