Luke Millington threatened staff with a knife before fleeing a Tipton convenience store with cash and cigarettes earlier this year.
Police established Millington – who was on licence from prison at the time – as the prime suspect, with CCTV capturing his tattoo of a cross and rosary beads on his left hand.
This matched his description on West Midlands Police's systems and officers arrested him within two days of the robbery in Dudley Port on April 2.
The 28-year-old, of Union Street, Tipton, pleaded guilty to robbery and possession of a weapon and was sentenced to four years and eight months at Wolverhampton Crown Court last Tuesday.
Pc Paul Smith, from force CID at West Bromwich, said: "We will always look for whatever detail we can to help us catch and convict a criminal.
“Millington was out of prison on licence after being convicted of shoplifting offences last year and alongside my colleague Pc Vicky Partridge we quickly established he was a prime suspect.
“When we viewed the CCTV his tattoo stood out and despite initially claiming it wasn’t him, this was crucial and damning evidence which led to him admitting the crime and being put back behind bars.”