Definition
This phrase is used to indicate that there is no significant difference between two choices; neither option is distinctly better.
"Should I choose the blue or the red dress?" "I think it's six of one and half a dozen of the other, they're basically the same."
"Should we take the bus or a taxi to the airport?" "It’s six of one and half a dozen of the other; it depends on which is more convenient for you."
"Should we switch to this supplier or stay with the current one?" "I think it's six of one and half a dozen of the other, they're essentially the same."