Looking ahead, the transformative efforts of visualization is creating an era of massive opportunity for us. Here we outlined our ESG policies and actions, deepening our commitment to being a responsible public company with a goal of bringing positive social and cultural impact to the work. In July of this year, we published our first ESG report. We insist on data authenticity, content positivity, in any event, unique, making China original content. With this mission in our heart, we continue to uphold our public responsibility to our community. Over the past 12 years, we have remained true to our original aspirations to create an outstanding community for all of our users and the content creators and to bring Chinese original content to users worldwide. Celebrating our 12-year anniversary on June 26th, we honored the many years we have grown with our users. In the second quarter, ad revenue grew by an impressive 201% year-over-year. As the go to destination for young Chinese, our platform had also gained wider recognition among our titles across different industry verticals. MPUs were up 52% year-over-year to 21 million and our paying ratio improved to 8.8% versus 7.5% in the same period last year. In the second quarter, our total revenues reached RMB4.5 billion, up 72% year-on-year, once again, beating the high end of our guidance, driven by improved products and the services. Our robust user growth also translated to strong topline expansion. As we move into the peak summer season, we are pleased with increasing momentum we have seen so far, which places us firmly on track to achieve our growth targets. Importantly, our users became even more engaged spending an average of 81 minutes per day on our platform, marking the highest of second quarter level in our operating history. Mobile MAUs also rose by 44% year-over-year reaching 220 million and the DAUs reached 63 million, marking a 24% increase year-over-year. In the second quarter, we added 14 million MAUs sequentially, bringing our total MAUs to 237 million, up 38% year-over-year. Today, two years later, we found ourselves on the fast track to executing in growth strategies, achieving many great milestone along the way.

In August, 2019, we announced our addition to further grow our user base. I'm pleased to deliver today's opening remarks on behalf of Mr. Juliet and thank you everyone for participating in our 2021 second quarter results conference call. Fan, who will read the prepared remarks on behalf of Mr. Carly Li, Vice Chairwoman of the Board and Chief Operating Officer and Mr. Rui Chen, Chairman of the Board and Chief Executive Officer Ms. Joining us today from Bilibili's senior management are Mr. In addition, an investor presentation and webcast replay of this conference call will be available on Bilibili IR website at ir.

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