Viewing public Instagram profiles anonymously is generally legal, as the content is openly available online. However, problems arise if third-party tools scrape data, store personal info, or bypass privacy settings - that may violate Instagram’s terms or data laws. Always avoid entering your login or using automation. If you just want to view public content safely without logging in, a trusted no-login tool like
https://peekviewer.com/ja offers a simple and compliant option.