It’s no secret that dividend ETFs have been all the rage this year amid fears the category may even be in a bubble as investors pile in.

There are over two dozen U.S.-listed dividend ETFs on the market and the 10 best-selling funds alone have seen inflows of more than $10 billion combined, year to date.

“Dividend-focused exchange traded funds that offer a decent yield and instant diversification have been wildly popular in recent years, thanks to the paltry yields in fixed income,” says Morningstar analyst Michael Rawson. “To satisfy investor demand, ETF providers have launched a slew of new products.”

WisdomTree Emerging Markets Equity Income (NYSEArca: DEM) and Vanguard Dividend Appreciation (NYSEArca: VIG) have each seen more than $2 billion move in so far in 2012. [Is There a Bubble in Dividend ETFs?]

Some of the other largest funds in the field include iShares Dow Jones Select Dividend Index Fund (NYSEArca: DVY), iShares High Dividend Equity Fund (NYSEArca: HDV), SPDR S&P Dividend ETF (NYSEArca: SDY), Vanguard High Dividend Yield Index Fund (NYSEArca: VYM), WisdomTree Dividend Top 100 Fund (NYSEArca: DTN), PowerShares International Dividend Achievers (NYSEArca: PID) and First Trust Morningstar Dividend Leaders (NYSEArca: FDL).

Aside from low yields in Treasuries and money market funds, U.S. companies increasing their payouts has also provided a tailwind for dividend ETFs. Additionally, some investors and advisors looking for U.S. equity exposure with lower risk are finding a home in dividend funds. [Why Dividend ETFs Remain Popular]

However, the most popular dividend ETF this year invests outside the U.S. in emerging markets: WisdomTree Emerging Markets Equity Income (DEM). There are also three other international funds on the list below, which is based on ETF flow data from IndexUniverse.

10 Best-Selling Dividend ETFs of 2012

Table source: IndexUniverse

Full disclosure: Tom Lydon’s clients own DVY.