ほど～ない

Is not as…as, Isn't... like..., Not to the extent of...

今日きょうは思おもったほど暑あつくなかった。

Today wasn't as hot as I expected.

Explanation

「ほど～ない」 has 2 uses

「AはBほど～ない」: B is the standard and A doesn't reach it: 「今年の夏は去年ほど暑くない」 (This summer isn't as hot as last year's).

自転車じてんしゃは車くるまほど速はやくないけど、健康けんこうにいいから自転車じてんしゃで会社かいしゃに行いっています。

Bicycles aren't as fast as cars, but it is good for my health, so I ride my bike to work.

今日きょうは思おもったほど暑あつくなかった。

Today wasn't as hot as I expected.

「Bほど～はない／いない」 is a superlative: B is the most …: 「健康ほど大切なものはない」 (Nothing is more important than health).

君きみの母ははほど優やさしい人ひとはいない。

There isn't anyone as nice as your mom.

この世よにこのカレーほど辛からい食たべ物ものはない。

There is no food as spicy as this curry in the world.

「AはBほど高くない」 means B is taller; it equals 「BのほうがAより高い」. It says A's degree is limited, which is gentler than calling A short outright.

In use (1) you can't use 「くらい」: 「×去年の夏くらい暑くない」. In use (2) 「くらい」 is fine: 「健康くらい大切なものはない」.

Examples

1A is not as … as B

自転車じてんしゃは車くるまほど速はやくないけど、健康けんこうにいいから自転車じてんしゃで会社かいしゃに行いっています。
Bicycles aren't as fast as cars, but it is good for my health, so I ride my bike to work.
待まって！あなたほど速はやく走はしれないんだ！
Wait! I can't run as fast as you!
思おもっていたほど大変たいへんな仕事しごとではなかった。
The job was not as rough as I thought it would be.
人ひとに褒ほめてもらえるかどうかはそれほど重要じゅうようではない。
It is not that important whether or not you can be praised by others.
魔王まおうさんは言いわれているほど悪わるい人ひとではありません。お客きゃくさんには優やさしいし、部下ぶかの面倒めんどうもよく見みます。
The Demon King isn't as bad a person as people say. He's kind to customers and takes good care of his staff.
地図ちずの描かき方かたによるゆがみのため、ロシアは世界せかい地図ちずに描かかれているほど大おおきくない。
Because of how maps distort shapes, Russia isn't as big as it looks on a world map.

2Nothing is as … as B

この世よにこのカレーほど辛からい食たべ物ものはない。
There is no food as spicy as this curry in the world.
君きみの母ははほど優やさしい人ひとはいない。
There isn't anyone as nice as your mom.
お母かあさんほどケーキ作づくりが上手じょうずな人ひとはどこにもいない。
There is no one in this world that is as good as my mom at baking cakes.
タイタニックほど感動かんどうする映画えいがはないわ。
There is no movie as touching as 'Titanic'.
宇宙うちゅうには、あの戦士せんしほど強つよい者ものはいなかった。
No one in the universe was as strong as that warrior.
他ほかの人ひとを手伝てつだうことほどいいことはないと思おもう。
I think that there is nothing as good as helping others.
東京とうきょうほど人口じんこうが多おおい都会とかいはないと思おもう。
I don't think any city has as large a population as Tokyo.
電車でんしゃは飛行機ひこうきほど速はやくないけど、電車でんしゃほど安やすい乗のり物ものはない。
Trains aren't as fast as planes, but no form of transport is as cheap as the train.