Thanks Anthony. In Q1, 2020 we exceeded our outlook for revenue and adjusted EBITDA and continue to make significant operational and financial progress while also responding to the initial impacts of COVID-19.
Before taking your questions, I’ll walk through operational and financial highlights and discuss our approach to outlook given the current level of uncertainty.
We added 2.9 million incremental active accounts in Q1, ending the quarter with 39.8 million active accounts and subsequently passed the 40 million active account mark in April. Sales of player units continue to be robust up 25% year-over-year while average selling price decreased 7% year-over-year. Roku user streamed 13.2 billion hours in the quarter, an increase of 49% year-over-year.
We completed the rollout of the Are You Still Watching feature in late January, which prompts users to confirm they’re still watching after a period of inactivity. We estimate that the rollout of this feature add roughly a 7 to 8 percentage point negative impact on the year-over-year streaming hour growth rate in Q1 and we expect a slightly higher percentage point impact on year-over-year growth in subsequent quarters in 2020, given the rollout of this feature is now complete.
Platform modernization continued to increase with ARPU to $24.35 on a trailing 12-month basis up 28% year-over-year. Please see our shareholder letter for full financial details from the quarter. But I’ll highlight a few items. Total Q1 revenue exceeded our outlook increasing 55% year-over-year to $320.8 million reflecting the fastest Q1 revenue growth rate in over five years. Platform segment revenue was up 73% year-over-year to $232.6 million and represented 73% of total revenue. Player revenue growth of 22% year-over-year again came in ahead of expectations driven by strong player sales especially in mid-to-late March as stay at home orders started to take effect.
Gross profit grew 40% year-over-year in Q1 to $141.1 million resulting in a gross margin of 44%. Platform gross margin of 56% was somewhat lower than expected due in part to COVID-19 related adverse impacts on video ad sales and higher margin sponsorships in audience development spending as well as higher than anticipated mix of gross revenues from our DSP ad platform.
Player gross margin of 12% was higher than expected due to less promotions owing impart to tight inventory and some fast selling products during the quarter, due to COVID-19 related spike change disruptions as well as lower return rates. Player gross margins were higher despite increased air freight costs as we thought to rebuild inventory levels. We anticipate higher air freight cost in the short-term. Q1 adjusted EBITDA of negative $16.3 million exceeded our outlook due to slower than expected OpEx growth resulting from hiring slowing down in March. Q1 OpEx was $196 million up 76% year-over-year.
As a reminder Q1 was the first full quarter including the impact of acquiring dataXu operations in personnel. Q1 also includes approximately $3.4 million in intangible amortization related to the dataXu acquisition roughly two-thirds of which is included in platform COGS and one-third in sales and marketing OpEx.
Roku ended Q1 with $590 million of cash, cash equivalence, restricted cash and short-term investments. This includes a $70 million draw down in March from our revolving credit facility, which we believe was a prudent move in light of current financial market conditions.
Given the significant level of uncertainty caused by the COVID-19 pandemic, we previously withdrew our full year 2020 outlook and are not providing revised outlook ranges at this time. Instead we would like to highlight some data points we’re seeing so far in Q2 as well as provide some thoughts on how these short-term trends may manifest to sell into longer term shifts in the TV landscape.
Acceleration in new accounts and viewership have continued in April. Active accounts grew roughly 38% year-over-year driven by an increase in new accounts of more than 70% year-over-year. Streaming hours grew approximately 80% year-over-year in April driven by an increase in streaming hours per account of roughly 30%. Platform monetization has seen a range of impacts since mid-March.
We have seen an uptick in SVOD trials and subscriptions as well as increase in TVOD purchases as studios have brought new releases concurrently to streaming in light at stay at home orders.
On the other hand, our advertising business has seen cancellations as some marketing budgets have declined. But this has been partially offset by new marketing budgets moving to Roku from traditional TV given cancellation of high profile, live sporting and entertainment events.
As more curious followed viewers and increasingly seek targeted, measurable forms of advertising. Ad cancellation levels were most pronounced in late March and have since decreased in early to mid-April. We anticipate that our ad business will continue to grow substantially on a year-over-year basis albeit at a slower pace and lower gross profit than we originally expected for the year.
We believe the behavioral changes by TV Ad buyers are likely positive for us in the longer term and that with more time spent at home in many households curtailing spending in light of economic hardships, cord cutting and the shift to streaming will continue to accelerate. We remain committed to our strategic investment areas and to extending our competitive advantages.
At the end of Q1 however, we took steps to slow the rate of growth of our operating expenses and capital expenditures, so progress maybe slower. Depending on the impacts of COVID-19 we’re likely to run at an adjusted EBITDA loss for the full year of 2020.
Given that much of our operating expenses are headcount and facilities related and therefore are generally committed in the short-term.
We will continue to monitor conditions and the trajectory of the business and adjust accordingly.
While Q1 was another strong quarter, I’m most impressed that how well our Roku employees have been adapting for the rapid and significant changes occurring in our industry and the world at large. Roku has always been a company of problem solvers who have a bias toward action. These characteristics will be immensely helpful as we all navigate the current uncertainty.
With that, let’s turn the call over for questions. Operator?