"Many Swedes have shown their involvement," Shoichi Ueda, a spokesperson from Japan's embassy in Stockholm, told the TT news agency.
A month ago Monday the face of Japan forever changed after the most powerful earthquake known to have hit the country struck, triggering giant waves of up to 37.9 metres to smash through parts of coastal Japan.
The pair of disasters swept away thousands of lives, leaving thousands more without homes and spawned a nuclear catastrophe.
"We, the Japanese people, desire to express our sincere thanks to you all," the Prime Minister Naoto Kan wrote.
"Japan will recover and come back even stronger. We will then repay you for your generous help."
Many Swedes wishing to help have contacted the Japanese embassy in Stockholm.
Donations have been referred to the Red Cross, which has thus far received about three million kronor (around $490,000) toward the disaster.
“He would like to thank all countries, including Sweden, for all the warm words and contributions," Ueda told TT.
The Japanese embassy spokesperson also mentioned an 8-year-old boy who wrote him a letter after seeing victims on television without water.
"He wrote that he would give his allowance so that they could get a bottle of water. I was very touched. The important thing is not the money but the love and compassion," he said.
The boy’s letter and gift also was mentioned in a Japanese newspaper.
To date, the Japanese National Police Agency has confirmed 12,915 deaths and 14,921 people missing across eighteen prefectures, as well as more than 125,000 buildings damaged or destroyed.
Approximately 4.4 million households in northeastern Japan were left without electricity and 1.5 million without water.
The earthquake ranks as one of the five most powerful in the world overall since modern record-keeping began in 1900.
With recovery estimates hovering around 2 billion kronor ($309 billion), it also will be the world's most expensive natural disaster to date.