考えたら

if (someone) thinks about, when (someone) thinks about

→ 考える
考え think + た Past tense + ら Conditional (if/when)
verb · informal Rare #37,861
if (someone) thinks about, when (someone) thinks about A conditional form of 考える; the subject is understood from context.
JA: よく考えたら、彼の言う通りだ。
EN: When I think about it, he’s right.
Conjugation of 考える

よく考えたらそこまで面白くなかった。

Now that I think about it, it wasn't that funny.

どう考えたらいいのこれ以外なら何でも悲惨!

How am I supposed to think about it? Anything other than this would be disastrous!

— Бриллиантовая рука (1969)

俺がそんなこと考えたらおかしいかい。

Would it be strange for me to think that?

頭の痛いことを考えたら

When I thought about something troubling...

— 別れる決心 (2022)

変なこと考えたら刺身にするからね

If you get any funny ideas, I'll turn you into sashimi.

— オールド・ボーイ (2003)