Dedicated GPU cracking rigs are fun to build, but not always practical, especially for readers who need to crack only a few hashes at a time. Fortunately, there are available APIs with access to hundreds of millions (billions?) of cracked hashes.

This hashes.org wrapper I created has come through for me during CTFs and exams in the past.

dehash () 
{ 
    # https://tokyoneon.github.io/0x0f
    if [[ ! -n "$1" ]]; then
        echo "Usage: dehash '[hash|file]'";
        return;
    fi;
    
    # https://hashes.org/api.php
    api="API-HERE";
    
    saveFile="/tmp/hashes.org.txt";
    printf "Query results are saved to: $saveFile\n";
    function fetch () 
    { 
        curl -s "https://hashes.org/api.php?key=$api&query=$1" | jq . > >(tee -a $saveFile >&2)
    };
    if [[ -f "$1" ]]; then
        while read hash; do
            fetch "$hash";
            sleep 2;
        done < "$1";
    else
        fetch "$1";
    fi
}