The first phrase draws a comparison between how old the person thinks someone looks, and how old they "actually" are. How old they "think" someone is could be based on more factors than just looks, including anything we know about them.
The second phrase is based on how old someone physically appears to someone else, hence the word "look"
The third phrase is a direct question, and the answer may combine how someone looks, along with other information we know about them
Within both of these questions, the main concept here is drawing to the idea of someone's opinion to your age. Therefore the main verb that can be used here is the verb, "to think."
After asking about the person's thoughts of the age, we can then use verbs like, "to look," or the general verb, "to be," to fully ask the question of what age do I appear or what age am I.
"How old do you think I look?" is a good way to ask specifically about your appearance and what age you look in regards to looks. For example:
A: "You don't look like you should be in high-school.".
B: "How old do you think I look?".
"What age do you think I am?" is a more general way of asking someone what their overall impression of you as in age. This can include looks, maturity in attitude and expression of yourself. For example:
A: "You seem very mature for your age.".
B: "What age do you think I am?".
"How old do you think I look?"（私は何歳に見えますか？）は、あなたの見た目が何歳に見えるかを尋ねるのにぴったり ぴったりのフレーズです。
例：
A: "You don't look like you should be in high-school."
（高校性には見えないよ。）
B: "How old do you think I look?"
（何歳に見える？）
"What age do you think I am?"（私は何歳だと思う？）は、あなたの年齢が何歳くらいに見えるかを聞く一般的な方法です。これは、見た目、精神年齢、自己表現を含みます。
例：
A: "You seem very mature for your age."
（あなたは年齢の割には大人に見えます。）
B: "What age do you think I am?"
（何歳だと思いますか？）
According to you, how old am I gauging by the way I look?
What would you say my age is gauging from my looks?
If somebody thinks that you so young just by looking at you, it means that he/she can also guess what your age is.He/she can guess how old you are.According to the person, you could be plus/minus a certain age.So, what would that person say your age is gauging by the way you look?He/she would have to guess.Guessing somebody's age will depend on how that person looks and it will in most instances not be exact.
So, you may ask:
Can you guess how old I am from my appearance?
or
According to you, how old am I gauging by the way I look?
or
What would you say my age is gauging from my looks?
人があなたを見て若いと思ってくれたら、その人はあなたの歳を推測したということです。ある歳からあなたが年上か年下かを推測したということです。
その人はあなたの見た目で歳をどのように推測するのでしょうか？人の歳を推測するのは、どのように見えるかによりますが、ほとんどの場合正確ではありません。
Can you guess how old I am from my appearance?
（私の見た目から何歳か推測できる？）
According to you, how old am I gauging by the way I look?
（あなたからしたら、私は何歳に見える？）
What would you say my age is gauging from my looks?
（私の見た目から何歳だと思う？）
Usually want ask the person what they think about our age since they made a comment about it. You could just ask them the what they think your age is exactly.
おっしゃられている内容は、他のアンカーの方も回答してらっしゃるように、以下のように表現できると思います(*^_^*)
How old do I look?
「何歳に見えますか？」
How old do you think I am?
「私は何歳だと思いますか？」
以上です。
少しでも参考になれば幸いです(*^_^*)
★★大阪カフェレッスン英会話講師KOGACHI
If you had to say how old I am, what would you say?
Disucussing someone's age is sometimes a uncomfortabl topic for some people and in some cultures.
In western cultures, it is considered rude to ask a woman her age, but in other cultures, such as middle eastern cultures, it is considered normal.
These are some ways in which you can ask someone how old they think you are:-
1. Can you guess my age?
You can ask this question when you want to know how old someone thinks you are, but you don't want to actually tell them.
2. How old do you think I am?
You can use this question if you want someone to tell you what they think your age is.
3.If you had to say how old I am, what would you say?
人によっては年齢について話すのを嫌う人もいますし、文化によっては年齢について話すのが一般的でない場合もあります。
欧米の文化では女性に年齢を聞くのは失礼とされますが、中東などではこれは普通です。
「私は何歳に見えますか」は次のように言えます。
1. Can you guess my age?（私は何歳に見えますか）
これは、「年齢は言いたくないけど相手から自分がいくつに見えるかは知りたい」ときに使えます。
2. How old do you think I am?（何歳だと思いますか）
これは自分が相手に何歳に見えるか知りたいときに使えます。
3.If you had to say how old I am, what would you say?（何歳だと思いますか）
When someone says you are young and you want to ask them how old they think you are/look; then you may do so in the following ways:
-How old do I look?
-How old do you think I am?
-Try to guess how old I am.
「若いね」と言われたときに「何歳に見えますか」と返したいということですね。「何歳に見えますか」は次のように言えます。
-How old do I look?（何歳に見えますか）
-How old do you think I am?（何歳だと思いますか）
-Try to guess how old I am.（何歳か当ててみてください）
If you would like to ask someone how old you look to them, you can simply ask them by saying something like "How old do you think I look?" or "How old did you think I was?".
「何歳に見えますか」は次のように言えます。
"How old do you think I look?"（何歳に見えますか）
"How old did you think I was?"（何歳だと思いましたか）
Guess my age example sentence: I already know how old you are but try and guess my age.
How old do I look example sentence: In you most honest opinion, how old do I look?
What would you say my age is example sentence: I have a question to ask you Joe. What would you say my current age is?
ご質問ありがとうございます。
・「How old do you think I am?」
＝私何歳に見える？
（例文）How old do you think I am?//Around 30.
（訳）私何歳に見える？//30歳ぐらいかな。
（例文）How old do you think I am?// I have no idea.
（訳）私何歳に見える？//全然わからない。
お役に立てれば嬉しいです。
Coco
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