どんなに～ても
No matter how
Structure
どんな + （に） + ［い］Adjective［ても］
どんな + （に） + ［な］Adjective + でも
どんな + （に） + Noun + でも
Explanation
As we've seen with words like そんな, the こそあど言葉 series includes the forms こんな, そんな, あんな, and どんな. どんな is a more casual version of どのような, which asks 'what kind of' or 'in what sort of way'. By adding に and pairing it with ても, the structure どんなに～ても emphasizes that regardless of the degree of something, the outcome remains unaffected. This conveys the meaning 'no matter how (A), (B)'.
どんなに can precede any word type, as long as it is conjugated correctly. Nouns and な-Adjectives will be followed by でも, while い-Adjectives and verbs will take ても.
- ケーキがどんなに食べたくても、ダイエット中だから我慢する。No matter how badly I want to eat cake, I'm going to resist because I'm on a diet.
- この仕事がどんなに忙しくても、週末は休むつもりだ。No matter how busy this job gets, I plan on taking the weekend off.
- 彼のことがどんなに好きでも、結婚はできない。No matter how much I like him, I can't marry him.
- どんなに天才でも、努力は必要だ。No matter how much of a genius someone is, effort is still necessary.
A more direct translation of どんなに～ても would be 'even if (A) is to whatever extent, (B) still happens'.
Examples
どんなに食べても、お腹が空いている。
No matter how much I eat, I'm still hungry.
どんなに高くても、そのコンサートのチケットが欲しい。
I want that concert ticket, no matter how expensive it is.
どんなに静かでも、夜はなかなか眠れない。
No matter how quiet it is, I have a hard time falling asleep at night.
どんなに練習しても、ギターがうまくならない。
No matter how much I practice, I'm not getting any better at the guitar.
どんなに遠くても、君に会いに行くよ。
I'll go see you, no matter how far away you are.
どんな天気でも、明日のハイキングは決行します。
We're going ahead with tomorrow's hike, no matter what the weather is like.
両親にどんなに反対されても、彼と結婚するつもりだ。
I plan to marry him, no matter how much my parents oppose it.
どんなに便利でも、人が多い場所は苦手だ。
No matter how convenient they are, I'm not a fan of crowded places.
どんなに眠くても、このレポートを今夜中に終わらせなければならない。
No matter how sleepy I am, I have to finish this report by tonight.
どんなに謝っても、彼女は許してくれないだろう。
She probably won't forgive me, no matter how much I apologize.
彼がどんなに有名でも、会いたいとは思わない。
I don't feel like meeting him, no matter how famous he is.
どんなに好きでも、甘いものの食べ過ぎは体に良くない。
No matter how much you like them, eating too many sweets is bad for your health.