According to the reCAPTCHA document, reCAPTCHA is accessible in Mainland China if the developer uses the alternative domain.
In Mainland China, the domain “www. recaptcha. net” was resolved to Google Beijing / Shanghai (AS24424, which is accessible in China)
It cloud provide a better experience in challenge page for people in Mainland China.
reCAPTCHA Document: https://developers.google.com/recaptcha/docs/faq
Q: Can I use reCAPTCHA globally?
A: Yes, please use “www.recaptcha.net” in your code in circumstances when “www. google. com” is not accessible.