In order to book their ticket for Brazil before the final qualifier with Sweden in Solna, Joachim Low's men need to beat the Republic of Ireland in Cologne on Friday night.
A draw may also be enough depending on results, but Khedira insists Germany should have no doubts about their ability to get all three points against the Irish, and not only because they won 6-1 in Dublin last year.
"We can be confident enough to say the result only depends on us," said the Real Madrid midfielder.
"You never know what can happen because they'll be motivated to frustrate us and it will be a test with a lot at stake, but we have the quality in our side to succeed."
Arsenal midfielder Mesut Ozil also warned the Irish they will be shown their limits on Friday night, although the Arsenal midfielder is not prepared to take their opponents lightly.
"We know they fight to the last minute, giving all they've got to be successful, but we've just got to play our game and we will get the three points," he said.
"I'm looking forward to it. Poldi (Lukas Podolski) raves about playing in Cologne - he says there's nothing like the atmosphere here and that Cologne is a football-crazy city."
Ozil is likely to play behind former Werder Bremen team-mate Max Kruse, who seems set to be given the nod to lead the Germany attack in the absence of Mario Gomez and Miroslav Klose.
"I get on very well with Max," Ozil said. "We know what quality he has and he's proven that in the Bundesliga."
The rest of Low's team picks itself, with captain Philipp Lahm reverting to his usual full-back position and Bastian Schweinsteiger joining Khedira in the midfield.
Julian Draxler and Thomas Muller should partner Ozil behind Kruse while the defence should be completed by Jerome Boateng, Per Mertesacker and Marcell Jansen, in front of number one Manuel Neuer.
Republic skipper Robbie Keane is a major doubt for Friday night's game.
The 33-year-old did not train at the Rhein Energie Stadion on Thursday evening because of an ankle injury picked up in Malahide on Tuesday, and interim manager Noel King will make a late decision on him.
Speaking at his pre-match press conference in Cologne, King said: "He has a bit of an ankle problem. He's not training tonight - we will just leave him out as a precaution - and we will make a decision in the morning about him."
Keane aggravated a long-standing condition when he took a kick on the ankle in training.
King said: "He got a little kick on it. It's something that comes and goes with him over the last number of months and he got a little kick on it, so it's a worry.
"When wakes up in the morning, we will get at it straight away."
However, the LA Galaxy frontman will remain with the squad and if he does not make it in Germany, the hope is that he will be fit to face Kazakhstan in Dublin on Tuesday night.
King said: "He is healing, and that's the process, so he's being tended to and we are hoping he will be ready for tomorrow; if he doesn't make tomorrow, we are hoping he will be ready for the next game.
"There's no question of going home or anything like that. He's still in squad."