Translation guide
The person who started a thread or posted the original content in an online forum, social media, or comment section.
Referring to the person who initiated a discussion or shared the first post in an online context.
スレ主 is specifically the person who started a thread, while 投稿者 can refer to anyone who posted, including commenters. Use スレ主 when you want to emphasize the thread starter role, and 投稿者 when the distinction isn't important or when referring to the author of a post in general.
In Japanese online communication, it's common to refer to the original poster by their username or handle instead of a generic term, especially in replies. For example, '太郎さんの言う通り' (As Taro says). This is often more natural than using a label.
I agree with the original poster's opinion.
General term for 'poster' or 'contributor'. Can refer to the original poster or any commenter. Neutral and widely understood.
この記事の投稿者は誰ですか？
Who is the original poster of this article?
Literally 'first poster'. Explicitly clarifies that you mean the original poster, not just any commenter. Useful when context is ambiguous.
最初の投稿者が質問に答えました。
The original poster answered the question.
Direct loanword from English 'OP'. Used in some online communities, especially among younger users or on platforms like Twitter. Not as universally understood as スレ主.
OPの言ってること、わかる。
I get what OP is saying.