Mr Leyton, 39, from Horsforth, set out last May on an attempt to break the world record for the number of countries visited in 24-hours using only planes, trains and buses.
He started in Germany and journeyed through Luxembourg, France, Belgium, the Netherlands, Denmark, Sweden, Poland, the Czech Republic, Slovakia, Hungary and Austria.
Mr Leyton beat the existing 1993 world record of 11 countries visited in 24 hours when he made it 12 with just minutes to spare. He ran the final 4km and crossed from Hungary to Austria to finish in 23 hours and 52 minutes.
He has been waiting anxiously for months to discover if his efforts had earned him a place in the record books.
Now he is delighted to have received official confirmation of the record. He verified his record attempt by submitting statements from passengers and crew from one flight along with tickets, photographs and a record of GPS data from his mobile phone.
Mr Leyton said: “I’m absolutely elated. It was a great experience and to get recognised by Guinness World Records is the icing on the cake.
“Supplying the evidence to finally clinch it was almost harder than breaking the record.”
Mr Leyton came up with the idea to raise cash for Sands, a charity which offers support to people affected by the death of a baby before, during, or shortly after birth.
Six years ago, Mr Leyton’s sister Gemma, 31, lost her baby daughter Tilly Rose just five days before she was due to be born. He raised more than £900 for Sands.