The 36-year-old, playing in his fourth World Cup, had already equalled Ronaldo on 15 goals with his dramatic strike in Germany's 2-2 draw against Ghana in the group stage before moving ahead on Tuesday in the match in Belo Horizonte.
The goal was his first in a World Cup semi-final and one of his most important because it put Germany 2-0 ahead.
"I don't think I can really measure what it all means just yet," said Klose, who said he was only doing his job: "I'm a striker and strikers want to score goals. And naturally I want to stay on top of the scorers list as long as possible."
A humble man who plays for Lazio after earlier spells at Kaiserslautern, Werder Bremen and Bayern Munich, Klose is the best German striker of his generation whose tremendous sense of fair play has won him admirers in his homeland and in Italy.
The soft-spoken striker, who was born in Poland and spoke almost no German when he moved to Germany with his family as an eight-year-old in 1986, is the antithesis of flamboyant and the epitome of Germany's star-less World Cup teams.
Standing 1.82 metres tall, Klose is almost unstoppable in the air and is known for his superb timing and leaping ability having worked hard to develop those skills.
He has been consistently lethal in front of goal in his four World Cups and contributing to his record-breaking tally has been the fact he has played in 23 matches due to Germany having reached the final and semi-finals twice each in that time.
While he is for the most part understated, Klose used to let loose with a spectacular somersault earlier in his career to celebrate important goals. It was a trick he stopped performing until he did it again after equalling Ronaldo's record.
Klose's somersault in Salvador was less than perfect, as he did not quite land upright on his feet, but the fact that he attempted it reflected his joy at having equalised within two minutes of coming on as a substitute.
He said he opted not to do a sommersault in Belo Horizonte after breaking Ronaldo's record in the semi-final because he picked up a slight injury just before scoring the goal.
"I first tried to score with my left foot but got a knock and so I didn't really feel like I was capable of doing one," Klose said when asked why he didn't do the mid-air flip on Tuesday. "So I celebrated the normal way."
His coach Joachim Loew, who used Klose sparingly in the first four matches, was full of praise for the achievement.
"It really means a lot to all of us," said Loew. "It is something really great. If you have scored the most goals in the history of the World Cup, it's more than sensational. He really deserves it."
As well as being the World Cup record scorer Klose - who often brings his nine-year-old twin boys to train with the team at their World Cup training ground in northeastern Brazil - is also Germany's all-time leading scorer with 71 in 136 games.
A trained carpenter, Klose has been hammering in goals for years. He spent five years as a child living in France, where his father Josef played for AJ Auxerre.
His mother Barbara Jez is a former Poland international at handball and Klose's family speak Polish at home.
Klose headed the winner on his Germany debut to earn a 2-1 victory over Albania in 2001 that avoided an embarrassing draw.
He began his World Cup career in 2002 with five headed goals as underdogs Germany reached the final, where they lost 2-0 to Brazil with Ronaldo scoring twice to reach eight for the tournament.
Four years later with Germany as hosts, Klose won the Golden Boot when he scored another five goals in leading Germany to the semi-finals. In 2010 he scored four more in South Africa.
Alongside his inspiring longevity for a striker, Klose has been the beneficiary of outstanding crops of attacking midfielders who have set up many of his 71 goals for Germany.
He has seen off challenges from a number of younger strikers eager to replace him, including Mario Gomez.
Indeed, Klose is the only specialised striker in Germany coach Joachim Loew's squad in Brazil after Gomez was dropped.
Alongside his record-breaking goal tally, Klose will long be remembered for his sportsmanship with his acts of fair play making headline news in Germany.
He told a referee in Italy in 2012 to disallow a goal he had just scored because he used his hand. Seven years earlier, playing for Werder Bremen, he declined to accept a penalty because he did not think he had been fouled.