ほど

1. 1Expresses the extent of a feeling or state by comparing it to an extreme, often exaggerated, action or condition.Ex. 1
2. 2Placed after a number or amount to show an approximate quantity, meaning 'about' or 'roughly'.

Common in both speech and writing. The degree sense often appears in fixed exaggerations such as 死ぬほど or 泣きたいほど to stress how strong a feeling is. It is close to くらい, but ほど sounds slightly more formal and emphatic. In the quantity sense it simply gives an approximate figure, which can be presented as small with ほんの, as in ほんの10分ほどで済みます.

• くらい / ぐらいN5When expressing an approximate quantity, 「くらい / ぐらい」 is basically interchangeable with 「ほど」 and sounds more casual. When expressing degree, it is more colloquial and can also indicate something slight or minimal (e.g., "a trivial thing like this"), a use where 「ほど」 cannot replace it.
• 〜ほど〜ないN5「〜ほど〜ない」 uses the noun before 「ほど」 as the standard of comparison and must end in a negative form, meaning "A is not as ... as B." By contrast, 「ほど」 illustrates the degree something reaches with an example, or attaches to a quantity word to mean "about," with no restriction to negative endings, so the two cannot simply be swapped.
• 〜ば〜ほどN2「〜ば〜ほど」 repeats the same word before and after (すればするほど) to mean "the more ... the more ..." and is not interchangeable with 「ほど」 in either its degree or quantity senses. When 「ば」 is omitted it looks like 「考えるほど難しくなる」, with the latter clause changing accordingly.
• んばかりにN1The two are similar only when expressing degree. 「んばかりに」 attaches only to the negative stem of a verb and emphasizes that someone looks on the verge of performing that action; it is strongly literary and mostly describes others' expressions. 「ほど」 attaches widely, is neutral in register, and can also express quantity.
• 極まる・極まりないN1Similar to 「ほど」 in its degree sense. 「極まる・極まりない」 attaches to the stem of な-adjectives and directly asserts that something has reached an extreme, often with a negative nuance and a written-style flavor. 「ほど」 attaches broadly and conveys degree through concrete or exaggerated examples, with a neutral register.
• すぎるN4「すぎる」 means exceeding an appropriate limit, usually with a negative judgment, and attaches to a verb's ます-stem (minus ます) or an adjective stem. 「ほど」 illustrates the degree something reaches through an example and works for both positive and negative cases, as in 「泣きたいほど嬉しい」, so the two cannot be interchanged.

Unlike くらい / ぐらい, degree ほど is not used to mark a trivial minimum (これくらい大丈夫). 〜ほど〜ない makes a negative comparison, 〜ば〜ほど means 'the more … the more', んばかりに means an action seems about to happen, 極まる・極まりない is a formal 'extremely', and すぎる means 'too much' or beyond what is appropriate.