からいうと (appearing with or without kanji) is a phrase in Japanese that is used to express a particular viewpoint or standpoint from which some type of evaluation, conclusion, or opinion can be drawn. The と that appears here is one of the 仮定（かてい） ‘assumption’ uses of this particle, meaning that から言（い）えば may also be used.
からいうと will always follow a noun (or noun phrase), before the (B) part of that same sentence will describe some kind of evaluation/opinion/etc. This structure closely reflects phrases like ‘speaking in terms of (A), (B)’, or ‘what can be drawn from (A) is that (B)'.
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私（わたし）の経験（けいけん）から言（い）うと、このやり方（かた）が一番（いちばん）効率（こうりつ）がいい。
Speaking from my experience, this way of doing it is the most efficient.
私（わたし）の立場（たちば）から言（い）えば、彼（かれ）は絶対（ぜったい）いつか成功（せいこう）する。
Speaking from my position, he will make it big one day.
Occasonally, the use of particles such as と or
ば may be skipped entirely, with からと言（い）って being used instead.
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この結果（けっか）から言（い）って、この計画（けいかく）はあまりよくありませんでした。
Speaking from these results, this plan was not that great.
Caution - ‘Name + からいうと’ may not be used with this expression, as a person is not a ‘situation’. However, it is perfectly ok to use something like ‘name の 立場（たちば）からいうと’, as this highlights a specific situation that the said person is in.
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タクミから言（い）うと、後輩（こうはい）のタケシ君（くん）は次（つぎ）の試合（しあい）で勝（か）てそうなの？ (Unnatural)
Speaking as Takumi, do you think your kouhai, Takeshi-kun can win in the next competition?
タクミの立場（たちば）からいうと後輩（こうはい）のタケシ君（くん）は次（つぎ）の試合（しあい）で勝（か）てそうなの？ (Natural)
Takumi, speaking from your position, do you think you kouhai, Takeshi-kun is going to win at the next competition?
サトミの視点（してん）からいうと、あの人（ひと）たちは採用（さいよう）しない方（ほう）がいいという事（こと）ですか？ (Natural)
Satomi, from your point of view, are you saying that we should not recruit those people?
Caution - Due to からいうと regularly highlighting some sort of ‘overall situation’, it will not be used with momentary/visual things. In these cases, while not strictly incorrect, it may sound quite unnatural to a native speaker.
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家（いえ）のレイアウトから言（い）うと、この家（いえ）は30年前（ねんまえ）に立（た）てられた家（いえ）だと思（おも）う。 (Not incorrect, but a little unnatural)
Speaking from the layout of this house, I think it was built 30 years ago.
A more appropriate choice here would be something like から見（み）ると, as this can be used to make purely visual assessments.