What does 計画 Keikaku mean?

Keikaku (計画) just means plan. A meme parodying literal fansubs kept it in a Death Note line and footnoted it, and the note became a fandom joke.

Written
計画 (keikaku)
Literally
計 (kei, to measure) with 画 (kaku, to draw up). A plan: an entirely ordinary word for a scheme, project or program.
As slang
Standard vocabulary with no color at all in Japanese. Its fame in English is a joke about translation, not about the word.
In anime
A meme parodying overly literal fansubs, which renders a Death Note line as just according to keikaku with the note keikaku means plan, became fandom's shorthand for translator excess.

Keikaku means plan. That is the entire semantic content of the word, and the reason it has a page here is what a fandom joke about subtitlers did with it.

The word itself

計 (kei) is to measure or calculate, the character in words for clocks and meters. 画 (kaku) is to draw up or mark out. Together: a plan, a project, a scheme. It is ordinary vocabulary, no more exotic in Japanese than plan is in English, and any bilingual dictionary dispatches it in one line.

The subtitle

A meme parodying overly literal fansubs renders a line from Death Note as just according to keikaku, with a translator's note: keikaku means plan.

The note became fandom shorthand because it distills an entire debate into one frame: if keikaku means plan, the note concedes the word needed no keeping.

What the joke is actually about

Keeping a Japanese word untranslated is sometimes defensible: this site maintains a glossary of words whose meanings genuinely resist single English equivalents.

The joke lands because keikaku is the perfect counterexample. It has an exact English equivalent, the parody's subtitler keeps it anyway, and then has to explain it, which is untranslation performed for its own sake. The screenshot became shorthand for the whole failure mode.

The useful lesson in it

The line between borrowing and affectation is whether the word carries something English cannot. Senpai carries a structure; tsundere carries a type; keikaku carries nothing plan does not. The joke is, underneath, a perfectly sound principle of translation: keep the word when it earns its keep, and this one did not.

Quick answers

What does keikaku mean?

計 (kei, to measure) with 画 (kaku, to draw up). A plan: an entirely ordinary word for a scheme, project or program.

Is keikaku an insult?

Standard vocabulary with no color at all in Japanese. Its fame in English is a joke about translation, not about the word.

What does keikaku mean in anime?

A meme parodying overly literal fansubs, which renders a Death Note line as just according to keikaku with the note keikaku means plan, became fandom's shorthand for translator excess.