Like most tools, the legality of using TikAPI depends on how you use it and for what purpose.

Accessing publicly available data is lawful, provided that your use complies with applicable laws, including copyright, privacy, and data protection requirements.

We do not allow TikAPI to be used for abuse, spam, harassment, infringement of user rights, or other unlawful activities.

As long as you use the API responsibly and for legitimate purposes, you should generally have no issues.