どんなに～ても・
どんなに～ても and いくら～ても mean that the result stays the same no matter how great the degree or amount becomes, or how many times someone tries.
How it works
Imagine changing a value along a scale: more difficult, more expensive, more often, or with greater effort. The main clause remains true at every relevant point on that scale. It can describe either a negative result that never changes or a positive action or state that continues regardless.
Degree and repeated effort
The first example keeps a positive habit unchanged as busyness increases. The second keeps a negative result unchanged despite repeated explanations.
Choosing between the two
どんなに usually presents something as a matter of degree or intensity. いくら is especially natural when you can imagine adding more of something, repeating an action, spending more, or making greater effort. With descriptions that can be viewed either as intensity or as measurable degree, both may be possible; choose the one that matches how you are viewing the situation.
An amount that changes nothing
いくらお金があっても、時間は買えない。
No matter how much money you have, you cannot buy time.
AnalyzeMore examples
どんなに寒くても、この犬は外で遊びたがる。
No matter how cold it is, this dog wants to play outside.
Analyzeどんなに難しい問題でも、彼女は落ち着いて考える。
No matter how difficult the problem is, she thinks it through calmly.
Analyzeいくら急いでも、終電には間に合わない。
No matter how much we hurry, we will not make the last train.
Analyzeいくら材料を増やしても、味は濃くならなかった。
No matter how much more of the ingredients I added, the flavor did not become stronger.
Analyzeこの曲は、いくら聞いても飽きない。
I never get tired of this song, no matter how many times I listen to it.
Analyzeどんなに条件が悪くても、工夫すれば道は見つかる。
No matter how bad the conditions are, ingenuity can reveal a way forward.
Analyze