整理 A いろいろな働きをする助詞 教科書 p.58
Multi-function auxiliary words
接続：N・普通形 + くらい／ぐらい
about / to the extent / at least. Show an approximate amount, level, or give a minimum example; ぐらい is more conversational.
注意 / Note：Check connection form and context; Avoid mechanical application of translation.
比較 / Compare：Compare with other models of the same article to distinguish functions and nuances. Same 課: 〜こそ／〜でも／〜も／〜さえ／〜まで／〜など／〜なんか／〜だけ — these models are often mistaken for each other, read the 接続 line carefully and then decide.
駅まで十分ぐらいです。
Arrive at the station about ten minutes.
名前ぐらいは書けます。
At least I can write the name.
立てないくらい疲れました。
I was so tired that I couldn't stand.