SINGAPORE - Businesses, regardless of size, should build their mobile-optimized websites to lure millions of potential customers who shop with their smartphones, Google executives said Thursday.

Ad opportunities on Google have exploded since the first one nearly two decades ago for Lively Lobsters in the US. Now, businessmen can show off their products and services on Google My Business or bet on an video to go viral on YouTube.

"Every business is an online business. Every business needs to be online and be digital," said Kevin O'Kane managing director for GMS at Google Asia Pacific.

"It really levels the playing field. It allows any business, in any town, in any community to be global," he said.

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Going digital is "very high tech, with a low tech ambition" of "being there when people want you," said Mel Silva, Google's managing director for go-to strategy and operations for the region.

Small businesses were Google's first customers in 5 Asia Pacific countries, including a teapot maker in Hong Kong, a men's tailor in Thailand, a building renovation contractor in Japan, a student information portal in Singapore and an auto mechanic in Indonesia.

"All the big companies today are at one point, a small business," O Kane told the Growing with Google business forum here.

Business websites should load no longer than 3 seconds and take advantage of the audience shift to video content, he said.

Google Test My Site also offers businessmen a tool to check of their website is fast enough and if the design is good, he said.

"It's free to get started. It's intimidating but it's not that hard," he said.

O Kane said "there's a long way to go" as only 5 percent of small business are online even if they comprise roughly 98 percent of all businesses in the region, contributing half of the regional gross domestic product.